It may not be easy to say whether this phenomenon is more connected with the law of similarity, or with that of variation. Youatt, in his work on cattle published by the Society for the Diffusion of Useful Knowledge, inclines to the former. He speaks of it as showing the universality of the application of the axiom that "like produces like"—that when this "may not seem to hold good, it is often because the lost resemblance to generations gone by is strongly revived." The phenomenon, or law, as it is sometimes called, of atavism,[15]or ancestral influence, is one of considerable practical importance, and well deserves careful attention by the breeder of farm stock.
Every one is aware that it is nothing unusual for a child to resemble its grandfather or grandmother or some ancestor still farther back, more than it does either its own father or mother. The fact is too familiar to require the citing of examples. We find the sameoccurrence among our domestic animals, and oftener in proportion as the breeds are crossed or mixed up. Among our common stock of neat cattle, (natives, as they are often called,) originating as they have done from animals brought from England, Scotland, Denmark, France and Spain, each possessing different characteristics of form, color and use; and bred, as our common stock has usually been, indiscriminately together, with no special point in view, no attempt to obtain any particular type or form, or to secure adaptation for any particular purpose, we have very frequent opportunities of witnessing the results of the operation of this law of hereditary transmission. So common indeed is its occurrence, that the remark is often made, that however good a cow may be, there is no telling beforehand what sort of a calf she may have.
The fact is sufficiently obvious that certain peculiarities often lie dormant for a generation or two and then reappear in subsequent progeny. Stockmen often speak of it as "breeding back," or "crying back." The cause of this phenomenon we may not fully understand. A late writer says, "it is to be explained on the supposition that the qualities were transmitted by the grandfather to the father in whom they weremaskedby the presence of some antagonistic or controlling influence, and were thence transmitted to the son in whom theantagonistic influence being withdrawn they manifest themselves." A French writer on Physiology says, if there is not inheritance of paternal characteristics, there is at least anaptitudeto inherit them, a disposition to reproduce them; and there is always a transmission of this aptitude to some new descendants, among whom these traits will manifest themselves sooner or later.[16]Mr. Singer, let us say, has a remarkable aptitude for music; but the influence of Mrs. Singer is such that their children inheriting her imperfect ear, manifest no musical talent whatever. These children however have inherited the disposition of the father in spite of its non-manifestation; and if, when they transmit what in them is latent, the influence of their wives is favorable, the grand-children may turn out musically gifted.
The lesson taught by the law of atavism is very plain. It shows the importance of seeking "thorough-bred" or "well-bred" animals; and by these terms are simply meant such as are descended from a line of ancestors in which for many generations the desirable forms, qualities and characteristics have beenuniformly shown. In such a case, even if ancestral influence does come inplay, no material difference appears in the offspring, the ancestors being all essentially alike. From this stand point we best perceive in what consists the money value of a good "pedigree." It is in the evidence which it brings that the animal is descended from a line all the individuals of which were alike, and excellent of their kind, and so is almost sure to transmit like excellencies to its progeny in turn;—not that every animal with a long pedigree full of high-sounding names is necessarily of great value as a breeder, for in every race or breed, as we have seen while speaking of the law of variation, there will be here and there some which are less perfect and symmetrical of their kind than others; and if such be bred from, they may likely enough transmit undesirable points; and if they be mated with others possessing similar failings, they are almost sure to deteriorate very considerably.
Pedigree is valuable in proportion as it shows an animal to be descended, not only from such as are purely of its own race or breed, but also from such individuals in that breed as were specially noted for the excellencies for which that particular breed is esteemed. Weeds are none the less worthless because they appear among a crop consisting chiefly of valuable plants, nor should deformed or degenerate plants, although they be true to their kind, ever be employed to produce seed.If we would have good cabbages or turnips, it is needful to select the most perfect and the soundest to grow seed from, and to continue such selection year after year. Precisely the same rule holds with regard to animals.
The pertinacity with which hereditary traits cling to the organization in a latent, masked or undeveloped condition for long after they might be supposed to be wholly "bred out" is sometimes very remarkable. What is known among breeders of Short-horns as the "Galloway alloy," although originating by the employment for only once of a single animal of a different breed, is said to be traceable even now, after many years, in the occasional development of a "smutty nose" in descendants of that family.
Many years ago there were in the Kennebec valley a few polled or hornless cattle. They were not particularly cherished, and gradually diminished in numbers. Mr. Payne Wingate shot the last animal of this breed, (a bull calf or a yearling,) mistaking it in the dark for a bear. During thirty-five years subsequently all the cattle upon his farm had horns, but at the end of that time one of his cows produced a calf which grew up without horns, and Mr. Wingate said it was, in all respects, the exact image of the first bull of the breed brought there.
Probably the most familiar exemplification of clearlymarked ancestral influence among us, is to be found in the ill-begotten, round-breeched calves occasionally, and not very unfrequently, dropped by cows of the common mixed kind, and which, if killed early, make very blue veal, and if allowed to grow up, become exceedingly profitless and unsatisfactory beasts; the heifers being often sterile, the cows poor milkers, the oxen dull, mulish beasts, yielding flesh of very dark color, ill flavor and destitute of fat. They are known by various names in different localities, in Maine as the "Whitten" and "Peter Waldo" breed, in Massachusetts as "Yorkshire" and "Westminster," in New York as the "Pumpkin buttocks," in England as "Lyery" or "LyeryDutch," &c., &c.
Those in northern New England are believed to be descended chiefly from a bull brought from Watervliet, near Albany, New York, more than forty years ago, (in 1818,) by the Shakers at Alfred, in York county, Maine, and afterwards transferred to their brethren in Cumberland county. No one who has proved the worthlessness of these cattle can readily believe that any bull of this sort would have been knowingly kept for service since the first one brought into the State, and yet it is by no means a rare occurrence to find calves dropped at the present time bearing unmistakable evidence of that origin.
It seems likely that this disagreeable peculiarity wasfirst brought into the country by means of some of the early importations of Dutch or of the old Durham breed.
Culley, in speaking of the Short-horns, inclines to the opinion that they were originally from Holland, and himself recollected men who in the early part of their lives imported Dutch cattle into the county of Durham, and of one Mr. Dobinson he says, he was noted for having the best breed of Short-horns of any and sold at high prices. "But afterwards some other persons of less knowledge, going over, brought home some bulls that introduced the disagreeable kind of cattle calledlyeryordouble lyered, that is, black-fleshed. These will feed to great weight, but though fed ever so long will not have a pound of fat about them, neither within or without, and the flesh (for it does not deserve to be called beef) is as black and coarse grained as horse flesh. No man will buy one of this kind if he knows any thing of the matter, and if he should be once taken in he will remember it well for the future; people conversant with cattle very readily find them out by their round form, particularly their buttocks, which are turned like a black coach horse, and the smallness of the tail; but they are best known to the graziers and dealers in cattle by thefeelortouchof the fingers; indeed it is this nice touch or feel of the hand that in a great measure constitutes the judge of cattle."
[15]From the LatinAtavus—meaning any ancestor indefinitely, as a grandmother's great grandfather.
[15]From the LatinAtavus—meaning any ancestor indefinitely, as a grandmother's great grandfather.
[16]"S'il n'y a pas héritage des caractéres paternels il y a donc au moinsaptitudeà en heriter, disposition à les reproduire, et toujours cette transmission de cette aptitude à des noveau descendants, chez lesquels ces mêmes caractéres se manifesteront tôt ou tard."—Longet's"Traite de Physiologie," ii: 133.
[16]"S'il n'y a pas héritage des caractéres paternels il y a donc au moinsaptitudeà en heriter, disposition à les reproduire, et toujours cette transmission de cette aptitude à des noveau descendants, chez lesquels ces mêmes caractéres se manifesteront tôt ou tard."—Longet's"Traite de Physiologie," ii: 133.
The relative influence of the male and female parents upon the characteristics of progeny has long been a fertile subject of discussion among breeders. It is found in experience that progeny sometimes resembles one parent more than the other,—sometimes there is an apparent blending of the characteristics of both,—sometimes a noticeable dissimilarity to either, though always more or less resemblance somewhere, and sometimes, the impress of one may be seen upon a portion of the organization of the offspring and that of the other parent upon another portion; yet we are not authorized from such discrepancies to conclude that it is a matter of chance, for all of nature's operations are conducted by fixed laws, whether we be able fully to discover them or not. The same causes always produce the same results. In this case, not less than in others there are, beyond all doubt, fixed laws, and the varying results which we see are easily and sufficiently accounted for by the existence of conditions or modifying influences not fully patent to our observation.
In the year 1825, the Highland Society of Scotland, proposed as the subject of prize essays, the solution of the question, "whether the breed of live stock connected with agriculture be susceptible of the greatest improvement from the qualities conspicuous in the male or from those conspicuous in the female parent?" Four essays received premiums. Mr. Boswell, one of the prize writers, maintained that it is not only the male parent which is capable of most speedily improving the breed of live stock, "but that the male is the parent which we can alone look to for improvement."
His paper is of considerable length and ably written—abounding in argument and illustrations not easily condensed so as to be given here, and it is but justice to add that he also holds that "before the breed of a country can be improved, much more must be looked to than the answer to the question put by the Highland Society—such as crossing, selection of both parents, attention to pedigree, and to the food and care of offspring."
And of crossing, he says, "when I praise the advantage of crossing, I would have it clearly understood that it is only to bring together animalsnot nearly relatedbut always ofthe same breed; never attempting to breed from a speed horse and a draught mare or vice versa." Crossing of breeds "may do well enough foronce, but will end in vexation, if attempted to be prolonged into a line."
Mr. Christian, in his essay, supports the view, that the offspring bears the greatest resemblance to that parent whether male or female, which has exerted the greatest sway of generative influence in the formation of the fœtus, "that any hypothesis which would assign a superiority, or set limits to the influence of either sex in the product of generation is unsound and inadmissible," and he thus concludes—"as therefore it is unsafe to trust to the qualities of any individual animal, male or female, in improving stock, the best bred and most perfect animals of both sexes should be selected and employed in propagation; there being, in short, no other certain or equally efficacious means of establishing or preserving an eligible breed."
Mr. Dallas, in his essay, starts with the idea that the seminal fluid of the male invests the ovum, the formation of which he ascribes to the female; and he supports the opinion, that where external appearance is concerned, the influence of the male will be discovered; but in what relates to internal qualities, the offspring will take most from the female. He concludes thus:—"When color, quality of fleece, or outward form is wanted, the male may be most depended on for these; but when milk is the object, when disposition,hardiness, and freedom from diseases of the viscera, and, in short, all internal qualities that may be desired, then the female may be most relied on."
One of the most valuable of these papers was written by the Rev. Henry Berry of Worcestershire, in which, after stating that the question proposed is one full of difficulty and that the discovery of an independent quality such as that alluded to, in either sex, would be attended with beneficial results, he proceeds to show, that it is not to sex, but to high blood, or in other words, to animals long and successfully selected, and bred with a view to particular qualifications, whether in the male or female parent, that the quality is to be ascribed, which the Highland Society has been desirous to assign correctly.
The origin of the prevalent opinion which assigns this power principally to the male, he explains by giving the probable history of the first efforts in improving stock. The greatest attention would naturally be paid to the male, both on account of his more extended services, and the more numerous produce of which he could become the parent; in consequence of which sires would be well-bred before dams. "The ideas entertained respecting the useful qualities of an animal would be very similar and lead to the adoption of a general standard of excellence, towards which it wouldbe required that each male should approximate; and thus there would exist among what may be termed fashionable sires, a corresponding form and character different from, and superior to, those of the general stock of the country. This form and character would in most instances have been acquired byperseverance in breeding from animals which possessed the important or fancied requisites, and might therefore be said to be almostconfirmedin such individuals. Under these circumstances, striking results would doubtless follow the introduction of these sires to a common stock; results which would lead superficial observers to remark, that individual sires possessed properties asmales, which in fact were only assignable to them asimprovedanimals."
The opinion entertained by some, that the female possesses the power generally ascribed to the male, he explains also by a reference to the history of breeding: "It is well known to persons conversant with the subject of improved breeding, that of late years numerous sales have taken place of the entire stocks of celebrated breeders of sires, and thus, the females, valuable for such a purpose, have passed into a great number of hands. Such persons have sometimes introduced a cow so acquired to a bull inferior in point of descent and general good qualities, and the offspring is known, inmany instances, to have proved superior to the sire by virtue of the dam's excellence, and to have caused a suspicion in the minds of persons not habituated to compare causes with effects, that certain females also possess the property in question."
The writer gives various instances illustrative of his views, in some of which the male only, and in others the female only, was the high-bred animal, in all of which the progeny bore a remarkable resemblance to the well-bred parent. He says, that where both parents are equally well bred, and of nearly equal individual excellence, it is not probable that their progeny will give general proof of a preponderating power in either parent to impress peculiar characteristics upon the offspring;—yet in view of all the information we have upon the subject, he recommends a resort to the best males as the most simple and efficacious mode of improving such stocks as require improvement, and the only proceeding by which stock already good can be preserved in excellence.
Mon. Giron[17]expresses the opinion that the relative age and vigor of the parents exercises very considerable influence, and states as the results of his observation, that the offspring of an old male and a young female resembles the father less than the mother inproportion as the mother is more vigorous and the father more decrepit, and that the reverse occurs with the offspring of an old female and a young male.
Among the more recent theories or hypotheses which have been started regarding the relative influence of the male and female parents, those of Mr. Orton, presented in a paper read before the Farmers' Club at Newcastle upon Tyne, on the Physiology of Breeding, and of Mr. Walker in his work on Intermarriage, as they both arrived to a certain extent, at substantially the same conclusions by independent observations of their own and as these seem to agree most nearly with the majority of observed facts, are deemed worthy of favorable mention.
The conclusions of Mr. Orton, briefly stated,[18]are, that in the progeny there is no casual or haphazard blending of the parts or qualities of the two parents, but rather that organization is transmitted by halves, or that each parent contributes to the formation of certain structures, and to the development of certain qualities. Advancing a step further, he maintains, that the male parent chiefly determines the external characters, the general appearance, in fact, the outward structure and locomotive powers of the offspring, as theframework, or bones and muscles, more particularly those of the limbs, the organs of sense and skin; while the female parent chiefly determines the internal structures and the general quality, mainly furnishing the vital organs, i.e., the heart, lungs, glands and digestive organs, and giving tone and character to the vital functions of secretion, nutrition and growth. "Not however that the male is without influence on the internal organs and vital functions, or the female without influence on the external organs and locomotive powers of their offspring. The law holds only within certain restrictions, and these form as it were a secondary law, one of limitations, and scarcely less important to be understood than the fundamental law itself."
Mr. Orton relies chiefly on the evidence presented byhybrids, the progeny of distinct species, or by crosses between the most distinct varieties embraced within a single species, to establish his law. The examples adduced are chiefly from the former. Themuleis the progeny of the male ass and the mare; thehinnythat of the horse and the she ass. Both hybrids are the produce of the same set of animals. They differ widely, however, in their respective characters—the mule in all that relates to its external characters having the distinctive features of the ass,—the hinny, in the same respects having all the distinctive features of the horse;while in all that relates to the internal organs and vital qualities, the mule partakes of the character of the horse, and the hinny of those of the ass. Mr. Orton says—"The mule, the produce of the male ass and mare, is essentially amodified ass: the ears are those of an ass somewhat shortened; the mane is that of the ass, erect; the tail is that of an ass; the skin and color are those of an ass somewhat modified; the legs are slender and the hoofs high, narrow and contracted, like those of an ass. In fact, in all these respects it is an ass somewhat modified. The body and barrel, however, of the mule are round and full, in which it differs from the ass and resembles the mare.
The hinny, on the other hand, the produce of the stallion and she ass, is essentially amodified horse. The ears are those of a horse somewhat lengthened; the mane flowing; the tail bushy, like that of the horse; the skin is finer, like that of the horse, and the color varies also, like the horse; the legs are stronger and the hoofs broad and expanded like those of the horse. In fact, in all these respects it is a horse somewhat modified. The body and barrel, however, of the hinny are flat and narrow, in which it differs from the horse and resembles the she ass.
A very curious circumstance pertains to the voice of the mule and the hinny. The mulebrays, the hinnyneighs. The why and wherefore of this is a perfect mystery until we come to apply the knowledge afforded us by the law before given. The male gives the locomotive organs, and the muscles are amongst these; the muscles are the organs which modulate the voice of the animal; the mule has the muscular structure of its sire, and brays; the hinny has the muscular structure of its sire, and neighs."
In connexion with these examples Mr. Orton refers to a special feature seen equally in the two instances, and which seems at first sight, a departure from the principle laid down by him. It is this, both hybrids, the mule and the hinny take after the male parents in all their external characters save one, which issize. In this respect they both follow the female parents, the mule being in all respects a larger and finer animal than its sire, the ass; the hinny being in all respects a smaller and inferior animal to its sire, the horse, the body and barrel of the mule being large and round, those of the hinny being flat and narrow; both animals being in these particulars the reverse of their respective sires, but both resembling their female parents.
In explanation of this seeming exception is adduced a well known principle in physiology, which is, that the whole bony framework is moulded in adaptation to the softer structures immediately related to it; the musclescovering it in the case of the limbs; and to the viscera in that of the great cavities which it assists in forming. Accordingly, in perfect accordance with the views above expressed, thegeneralsize and form which must be mainly that of thetrunk, will be determined by the size and character of the viscera of the chest and abdomen, and will therefore accord with that of the female parents by whom the viscera in question are chiefly furnished.
The foregoing are the most important of Mr. Orton's statements. He gives, however, numerous additional illustrations from among beasts, birds and fishes, of which we quote only the following:
"The mule and the hinny have been selected and placed first, because they afford the most conclusive evidence and are the most familiar. Equally conclusive, though perhaps less striking instances, may be drawn from other sources. Thus, it has been observed that when the Ancon or Otter sheep were allowed to breed with common ewes, the cross is not a medium between the two breeds, but that the offspring retains in a great measure the short and twisted legs of the sire."
Buffon made a cross between the male goat and the ewe; the resulting hybrid in all the instances, which were many, were strongly characteristic of the maleparent, more particularly in the hair and length of leg. Curious enough, the number of teats in some of the cases corresponded with those of the goat.
A cross between the male wolf and a bitch illustrates the same law; the offspring having a markedly wolfish aspect; skin, color, ears and tail. On the other hand, a cross between the dog and female wolf afforded animals much more dog-like in aspect—slouched ears and even pied in color. If you look at the descriptions and illustrations of these two hybrids, you will perceive at a glance that the doubt arises to the mind in the case of the first, 'what genus ofwolfis this?' whereas in the case of the second, 'what a curiousmongrel dog!'
The views of Mr. Walker in his work on Intermarriage, before alluded to, agree substantially with those of Mr. Orton,so far as regards crossing between different breeds; but they cover a broader field of observation and in some respects differ. Mr. Walker maintains that when both parents are of thesame breedthateither parent may transmit either halfof the organization. That when they are ofdifferent varietiesor breeds (and by parity of reasoning the same should hold, strongly, when hybrids are produced by crossing differentspecies) and supposing also that both parents are of equal age and vigor, that themalegives theback head and locomotive organsand thefemaletheface andnutritive organs—I quote his language: "when both parents are of the same variety,one parent communicates the anterior part of the head, the bony part of the face, the forms of the organs of sense(the external ear, under lip, lower part of the nose and eye brows being often modified)and the whole of the internal nutritive system, (the contents of the trunk or the thoracic and abdominal viscera, and consequently the form of the trunk itself in so far as that depends on its contents.)
The resemblance to that parent is consequently found in the forehead and bony parts of the face, as the orbits, cheek bones, jaws, chin and teeth, as well as the shape of the organs of sense and the tone of the voice.
The other parent communicates the posterior part of the head, the cerebel situated within the skull immediately above its junction with the back of the neck, and the whole of the locomotive system; (the bones, ligaments and muscles or fleshy parts.)
The resemblance to that parent is consequently found in the back head, the few more movable parts of the face, as the external ear, under lip, lower part of the nose, eyebrows, and the external forms of the body, in so far as they depend on the muscles as well as the form of the limbs, even to the fingers, toes and nails. * *
It is a fact established by my observations that in animals of thesame variety, either the male or the femaleparentmay giveeither series of organsas above arranged—that iseitherforehead and organs of sense, together with the vital and nutritive organs,orback head, together with the locomotive organs."
To show that among domesticated animals organization is transmitted by halves in the way indicated, and that either parent may give either series of organs, he cites among other instances the account of the Ancon sheep. "When both parents are of the Ancon or Otter breed, their descendants inherit their peculiar appearance and proportions of form. When an Ancon ewe is impregnated by a common ram, the progeny resembles wholly either the ewe or the ram. The progeny of a common ewe impregnated by an Ancon ram follows entirely in shape the one or the other without blending any of the distinguishing and essential peculiarities of both.
'Frequent instances have occurred where common ewes have had twins by Ancon rams; when one exhibited the complete marks and features of the ewe and the other of the ram. The contrast has been rendered singularly striking when one short legged and one long legged lamb produced at a birth have been sucking the dam at the same time.'
As the short and crooked legs or those of opposite form, here indicate the parent giving the locomotivesystem, it is evident that one of the twins derived it from one parent and the other twin from the other parent;—the parent not giving it, doubtless communicating in each case, the vital or nutritive system."
Where the parents are of different varieties or species, Mr. Walker says, "The second law, namely, that ofCROSSING, operates where each parent is of adifferent breed, and where, supposing both to be of equal age and vigor themalegives theback headandlocomotive organs, and thefemalethefaceandnutritive organs."
After giving numerous illustrations from facts and many quotations from eminent breeders, he says, "thus, in crosses of cattle as well as of horses, the male, except where feebler or of inferior voluntary and locomotive power, gives the locomotive system, the female the vital one."
W.C. Spooner, V.S., one of the most eminent authorities of the present day on this subject, and writing within the past year in the Journal of the Royal Agricultural Society, says:—"The most probable supposition is, that propagation is done by halves, each parent giving to the offspring the shape of one half of the body. Thus the back, loins, hind-quarters, general shape, skin and size follow one parent; and the fore-quarters, head, vital and nervous system, the other; and we may go so far as to add, that the former in thegreat majority of cases go with the male parent, and the latter with the female. A corroboration of this fact is found in the common system of putting an ordinary mare to a thorough-bred horse; not only does the head of the offspring resemble the dam but the forelegs likewise, and thus it is fortunately the case that the too-frequently faulty and tottering legs of the sire are not reproduced in the foal, whilst the full thighs and hind quarters which belong to the blood-horse are generally given to the offspring. There is however a minority of cases in which the opposite result obtains. That size is governed more by the male parent there is no great difficulty in showing; familiar examples may be found in the pony-mare and the full sized horse, which considerably exceed the dam in size. Again, in the first cross between the small indigenous ewe and the large ram of another improved breed—the offspring is found to approach in size and shape very much to the ram. The mule offspring of the mare also much resembles both in size and appearance its donkey sire. These are familiar examples of the preponderating influence of the male parent, so far as the external form is considered. To show however that size and hight do not invariably follow the male, we need go no further for illustration than the human subject. How often do we find that in the by no means unfrequent case of theunion of a tall man with a short woman, the result in some instances is that all the children are tall and in others all short; or sometimes that some are short and others tall. Within our own knowledge in one case, where the father was tall and the mother short, the children, six in number, are all tall. In another instance, the father being short and the mother tall, the children, seven in number, are all of lofty stature. In a third instance, the mother being tall and the father short, the greater portion of the family are short. Such facts as these are sufficient to prove that hight or growth does not exclusively follow either the one parent or the other. Although this is the case, it is also a striking fact that the union of tall and short parents rarely, if ever, produces offspring of a medium size—midway, as it were, between the two parents.
Thus, in the breeding of animals, if the object be to modify certain defects by using a male or female in which such defects may not exist, we cannot produce this desired alteration; or rather it cannot be equally produced in all the offspring, but can only be attained by weeding out those in whom the objectionable points are repeated. We are, however, of opinion that in the majority of instances, the hight in the human subject, and the size andcontourin animals, is influencedmuch more by the malethan the female parent—and on theother hand, that the constitution, the chest and vital organs, and the forehand generally more frequently follow the female."
Dr. Carpenter, the highest authority in Physiology, says "it has long been a prevalent idea that certain parts of the organism of the offspring" are derived from the male, and certain other parts from the female parent; and although no universal rule can be laid down upon this point, yet the independent observations which have been made by numerous practical breeders of domestic animals seem to establish that such atendencyhas a real existence; the characters of theanimalportion of the fabric being especially (but not exclusively) derived from the male parent, and those of theorganicapparatus being in like manner derived from the female parent. The former will be chiefly manifested in the external appearance, in the general configuration of the head and limbs, in the organs of the senses (including the skin) and in the locomotive apparatus; whilst the latter show themselves in the size of the body (which is primarily determined by the development of the viscera contained in the trunk) and in the mode in "which the vital functions are performed."
On the whole it may be said that the evidence both from observation and the testimony of the best practical breeders goes to show that each parent usuallycontributes certain portions of the organization to the offspring, and that each has a modifying influence upon the other. Facts also show that the same parent does not always contribute the same portions, but that the order is reversed. Now, as no operation of nature is by accident, but by virtue oflaw, there must be fixed laws here, and there must also be, at times, certain influences at work to modify the action of these laws. Where animals are of distinct species, or of distinct breeds, transmission is usually found to be in accordance with the rule above indicated, i.e. the male gives mostly the outward form and locomotive system, and the female chiefly the interior system, constitution, &c. Where the parents are of the same breed, it appears that the portions contributed by each are governed in large measure by the condition of each in regard to age and vigor, or by virtue of individual potency or superiority of physical endowment.
Thispotencyor power of transmission seems to be legitimately connected with high breeding, or the concentration of fixed qualities obtained by continued descent for many generations from such only as possess in the highest degree the qualities desired. On the other hand it must be admitted that there are exceptional cases not easily accounted for upon any theory, and it seems not improbable that in these the modifyinginfluences may be such as to effect what may approximate a reconstruction or new combination of the elements, in a manner analogous to the chemical changes which we know take place in the constituents of vegetables, as for instance, we find that sugar, gum and starch, substances quite unlike in their appearance and uses, are yet formed from the same elements and in nearly or precisely the same proportions, by a chemistry which we have not yet fathomed. Whether this supposition be correct or not, there is little doubt that if we understood fully all the influences at work, and could estimate fairly all the data to judge from, we might predict with confidence what would be the characteristics of the progeny from any given union.
Practically, the knowledge obtained dictates in a most emphatic manner that every stock-grower use his utmost endeavor to obtain the services of the best sires; that is,the best for the end and purposes in view—that he depend chiefly on the sire for outward form and symmetry—that he select dams best calculated to develop the good qualities of the male, depending chiefly upon these for freedom from internal disease, for hardihood, constitution, and generally for all qualities dependent upon the vital or nutritive system.
The neglect which is too common, and especially in breeding horses, to the qualities of the dam, miserablyold and inferior females being often employed, cannot be too strongly censured. In rearing valuable horses the dams are not of less consequence than the sires, although their influence upon the progeny be not the same. This is well understood and practiced upon by the Arab, who cultivates endurance and bottom. If his mare be of the true Kochlani breed he will part with her for no consideration whatever, while you can buy his stallion at a comparatively moderate price. The prevalent practice in England and America of cultivating speed in preference to other qualities, has led us to attach greater importance to the male, and the too common neglect of health, vigor, endurance and constitution in the mares has in thousands of cases entailed the loss of qualities not less valuable, and without which speed alone is of comparatively little worth.
[17]In his work, "De la Generation," Paris, 1828.
[17]In his work, "De la Generation," Paris, 1828.
[18]Quoted, in part, from a paper by Alex. Harvey, M.D., read before the Medical Society of Southampton, June 6th, 1854.
[18]Quoted, in part, from a paper by Alex. Harvey, M.D., read before the Medical Society of Southampton, June 6th, 1854.
With regard to the laws which regulate the sex of progeny very little is known. Many and extensive observations have been made, but without arriving at any definite conclusions. Nature seems to have provided that the number of either sex produced, shall be nearly equal, but by what means this result is attained, has not been discovered. Some physiologists think the sex decided by the influence of the sire, others think it due to the mother. Sir Everard Home believed theovumor germ, previous to impregnation to be of no sex, but so formed as to be equally fitted to become either male or female, and that it is the process of impregnation which marks the sex and forms the generative organs; that before the fourth month the sex cannot be said to be confirmed, and that it will prove male or female as the tendency to the paternal or maternal type may preponderate.
Mr. T.A. Knight[19]was of opinion that the sex of progeny depended upon the influence of the femaleparent. He says, "The female parent's influence upon the sex of offspring in cows, and I have reason to believe in the females of our other domestic animals, is so strong, that it may, I think, be pronounced nearly positive," He also says, "I have repeatedly proved that by dividing a herd of thirty cows into three equal parts, I could calculate with confidence upon a large majority of females from one part, of males from another, and upon nearly an equal number of males and females from the remainder. I have frequently endeavored to change the habits by changing the male without success." He relates a case as follows:—"Two cows brought all female offspring, one fourteen in fifteen years, and the other fifteen in sixteen years, though I annually changed the bull. Both however produced one male each, and that in the same year; and I confidently expected, when the one produced a male that the other would, as she did."
M. Giron, after long continued observation and experiment, stated with much confidence, that the general law upon this point was, that the sex of progeny would depend on the greater or less relative vigor of the individuals coupled. In many experiments purposely made, he obtained from ewes more males than females by coupling very strong rams with ewes either too young, or too aged, or badly fed, and more females thanmales by a reverse choice in the ewes and rams he put together.
Mon. Martegoute, formerly Professor of Rural Economy, in a late communication to the "Journal D'Agriculture Pratique," says that as the result of daily observations at a sheepfold of great importance, that of the Dishley Mauchamp Merinos of M. Viallet at Blanc, he has, if not deceived, obtained some new hints. He states that Giron's law developed itself regularly at the sheepfold in all cases where difference of vigor was observed in the ewes or rams which were coupled; but he adds another fact, which he had observed every year since 1853, when his observations began. This fact consists—
First, In that at the commencement of the rutting season when the ram is in his full vigor he procreated more males than females.
Second, When, some days after, and the ewes coming in heat in great numbers at once, the ram being weakened by a more frequent renewal of the exertion, the procreation of females took the lead.
Third, The period of excessive exertion having passed, and the number of ewes in heat being diminished, the ram also found less weakened, the procreation of males in majority again commenced."
In order to show that the cause of such a result isisolated from all other influences of a nature to be confounded with it, he gives the details of his observations in a year when the number of births of males and females were about equal. He also goes on to say, that, "at the end of each month all the animals at the sheepfold are weighed separately, and thanks to these monthly weighings, we have drawn up several tables from which are seen the diminution or increase in weight of the different animals classed in various points of view, whether according to age, sex or the object for which they were intended.
Two of these tables have been appropriated to bearing ewes—one to those which have borne and nursed males and the other to those which have borne and brought up females. The abstract results of these two tables have furnished two remarkable facts.
First, The ewes that have produced the female lambs are, on an average, of a weight superior to those that produced the males; and they evidently lose more in weight than these last during the suckling period.
Second, The ewes that produce males weigh less, and do not lose in nursing so much as the others.
If the indications given by these facts come to be confirmed by experiments sufficiently repeated, two new laws will be placed by the side of that which Giron de Bazareingues has determined by his observationsand experiments. On the one hand, as, at liberty, or in the savage state, it is a general rule that the predominance in acts of generation belongs to the strongest males to the exclusion of the weak, and as such a predominance is favorable to the procreation of the male sex, it would follow that the number of males would tend to surpass incessantly that of the females, amongst whom no want of energy or power would turn aside from generation, and the species would find in it a fatal obstacle to its reproduction. But, on the other hand, if it was true that the strongest females and the best nurses amongst them produce females rather than males, nature would thus oppose a contrary law, which would establish the equilibrium, and by an admirable harmony would secure the perfection and preservation of the species, by confiding the reproduction of either sex to the most perfect type of each respectively."