ORDER INSECTIVORA.

LOW’S PTILOCERQUE.ORDER INSECTIVORA.

LOW’S PTILOCERQUE.

Functions of the Insect-eaters in the Order of Nature—Their Leading Peculiarities—Classification—COLUGOS—Various Opinions regarding their Place—COLUGO,ORFLYINGLEMUR—ThePatagium—Parachute-like Membrane—Dentition—Offspring—Diet—BANGSRINGS—TANA—FERRUGINOUSBANGSRING—HORSFIELD’SBANGSRING—LOW’SPTILOCERQUE—SHORT-TAILEDBANGSRING—JUMPINGSHREWS—ELEPHANTSHREW—ALGERIANJUMPINGSHREW—PETRODROME—RHYNCHOCYON—HEDGEHOG—Characteristics—Distribution—Diet—Attacks Snakes and Vipers—Taste for Eggs and Game—Its “Spiny Skin”—“Rolled up”—Enemies—Female and Young—LONG-EAREDHEDGEHOG—COLLAREDHEDGEHOG—BULAU—TANRECS—TANREC—TENDRAC—TELFAIR’STENDRAC—RICETENDRAC—EAREDEARTHSHREW—AGOUTA—ALMIQUI—WESTAFRICANRIVERSHREW

INthe grand economy of nature small things play sometimes very considerable parts; and the innumerable hosts of insects, making up by their numbers for their individual insignificance, are of very great importance in a great variety of fashions. One of their most striking functions is undoubtedly the checking of vegetable growth. They attack plants in all parts—in the roots, the stem, the branches, the leaves, and the flowers and fruit—in this way, while merely obeying their own appetites, imposing a constant check upon the increase of vegetation; and being for the most part specially confined to particular plants or groups of plants, they assist materially in preserving the balance of power in the vegetable world. At the same time, it must be borne in mind that there is the same tendency in insects, as in any other group of organisms, to inordinate increase. The checkers thus need a check in their turn, and the number of other creatures whose business it seems to be to keep down the undue multiplication of insects is exceedingly great.

We have seen that among the Mammalia the Bats for the most part have this duty imposed upon them. They attack the winged armies of perfect insects in the air, and must cut off an enormous number of potential parents of plant-eating larvæ. But there are a great many insects whichseldom or never rise into the air, and the larvæ of those which are aerial in their perfect state are of necessity confined to the ground or the vegetation growing on it; these are not without their Mammalian enemies. Many Mammals of the Carnivorous and Marsupial orders feed wholly or partially upon insects; but there is one order most of the species of which are exclusively, or almost exclusively, confined to a diet of terrestrial insects, worms and “such small deer,” and which has consequently received the name of Insectivora, or “the insect-eaters.” On trees, on the ground, and even beneath its surface, and in the water, these animals chase insects and their larvæ; and if they diversify their diet with worms and other invertebrates, or by attacking and devouring frogs, fishes, and small birds and Mammalia, or even in some cases feed chiefly upon such articles, or on fruit, the predominating taste for insects among the members of the order may justify the name.

SKELETON OF SHREW.

The Insectivora are in many respects related to the Bats, and in some cases show a sort of affinity to the lower Quadrumana. In appearance many of them show analogy to different families of Rodents, or gnawing Mammals, the Shrews especially exceedingly mouse-like in their aspect; but, as might be expected from the difference in the habits, and especially in the diet of the animals, the simple inspection of the teeth is always sufficient to distinguish the members of these two orders.

DENTITION OF HEDGEHOG.

The leading peculiarities of the Insectivora may be briefly indicated, with reference to the groups which approach them most closely in certain points of structure. The limbs are all organised for walking or digging, the fore limbs never being modified, as in the Bats, into organs of flight, and the two bones of the fore-arm (radiusandulna) are always more or less distinct. There is no opposable thumb, either on the fore or the hind feet. The teeth, which are always encased in enamel, are of the usual three kinds—incisors, canines, and molars[251]—and the dentition generally resembles that of the strictly Insectivorous Bats, the molarsespecially being similarly furnished with several sharp cusps or points, which are regarded as characteristic of Insect-eating Mammals. All the teeth are implanted in the jaws by roots.

In the development of the tail, and the nature of the covering of the skin, the Insectivora present considerable diversities, which will be referred to hereafter. Their feet generally consist of five toes, all armed with claws, and nearly all are plantigrade—that is to say, they apply the whole, or nearly the whole, of the sole of the foot to the ground in walking. With a single exception (Potamogale, which is rather anomalous in some other respects), all the Insectivora are provided with complete clavicles, or collar-bones—a character which serves to distinguish them from the Carnivora, in which the collar-bones are either deficient or imperfectly developed. The teats are generally numerous, and situated on the abdomen, the only exceptions being the anomalous Colugo, or so-called Flying Lemur, and the Golden Moles, in which the teats are situated on the breast.

Zoologists are now pretty well agreed as to the classification of these animals, although there are still differences of opinion as to the best arrangement of the families, and some minor points. The classification here adopted is founded upon that proposed by Professor Mivart in 1871, and afterwards modified by Professor Theodore Gill. In this the whole order is divided into nine families, the first of which is so anomalous, and so divergent from all the rest in its characters, as to have led to its being treated as constituting a distinct sub-order (Dermoptera).

The animals which constitute this family, now regarded as constituting only two species (although the right even of one of these to specific rank is somewhat doubtful), are in truth amongst the most anomalous of Mammals. In their characters they present the most singular resemblances to at least three orders of Mammalia, in which they have been successively placed by various zoologists. Discovered by the Dutch voyagers of the seventeenth century in the luxuriant forests of the Eastern islands, their general Lemur-like aspect led the naturalists of those days to class them with those creatures, and Camelli, the distinguished botanist, gave them the name ofGaleopithecus, which became in Petiver’s hands, “Cato-simius volans,” or the Flying Cat-Monkey. Seba left out the Monkey, and called the animal simply the Flying Cat of Ternate (Felis volans ternatea); whilst Bontius, laying undue weight on its so-called flying powers, regarded it as a Bat, and gave it the name ofVespertilio admirabilis. Linnæus accepted the Lemur hypothesis, and placed the animal in his genusLemur, under the name ofLemur volans, or the Flying Lemur, and this position it continued to hold for a very long time, although Pallas separated it from the true Lemurs under Camelli’s name ofGaleopithecus. No one ever reverted to the notion that the Colugo was a Bat, but from time to time various naturalists have pointed out that in many of its characters it approached the Insectivora; and of late years the evidence in favour of its belonging to that order has been put forward so strongly, that nowadays nearly all zoologists regard it as an exceedingly aberrant member of the group, with more or less distinct tendencies towards the Bats and the Lemurs, and perhaps with some faint trace of the Marsupial about it. Mr. Wallace, speaking, of course, from the standpoint of the theory of evolution, says that “this animal seems, in fact, to be a lateral offshoot of some low form, which has survived during the process of development of the Insectivora, the Lemuroidea, and the Marsupials, from an ancestral type.” There is no doubt that the beast is sufficiently dissimilar from all other known Mammals to give a considerable air of probability to the assumption of its being a survivor from some earlier period of the earth’s history; but as it is here we must do the best we can with it, and its natural position is certainly between the true Insectivora and the Lemurs. As the characters of the family are founded virtually upon a single species, one description will serve.

The species known to the older naturalists is found in Malacca, Sumatra, and Borneo, where it inhabits the forests, climbing the trees like a Squirrel by the aid of its claws, and passing through the air from one tree to another by means of a membrane (patagium), which extends along the sides of thebody, and can be stretched by the extension of the limbs to which it is attached so as to act as a sort of parachute, which supports its owner after the same fashion as the very similar fold of skin that exists in the same position in the so-called Flying Squirrels and Flying Opossums. In the Colugo, however, this curious arrangement is carried further than in the other groups of Mammals just mentioned; for, as in the Bats, there is a distinct antebrachial membrane, stretching along the front of the arms from the wrists to the sides of the neck; and the space between the hind limbs is occupied by an ample triangular membrane, down the middle of which the long tail passes, and which is also stretched by the extension of the limbs. Even the toes are joined by membranes as far as the base of the claws, and this great development of the skin must be regarded as to a certain extent approximating the creature to the Bats. The whole of this fold of skin is clothed both above and beneath with hair; and although some observers have described the animal as moving its expanded membranes during flight, no approach to the peculiar action of the Bat’s wing can ever be made by it. The most striking point in which it exceeds the other parachute-bearing Mammals is the development of the membrane between the hind limbs, and this, by the action of the tail, may be made to exert a powerful influence upon the course of the animal during its so-called flights. Mr. Wallace, who had the opportunity of observing the Colugo in its native haunts, describes its flight as follows:—“Once, in a bright twilight,” he says, “I saw one of these animals run up a trunk in a rather open place, and then glide obliquely through the air to another tree, on which it alighted near its base, and immediately began to ascend. I paced the distance from the one tree to the other, and found it to be seventy yards, and the amount of descent I estimated at not more than thirty-five or forty feet, or less than one in five. This, I think, proves that the animal must have some power of guiding itself through the air, otherwise in so long a distance it would have little chance of alighting exactly upon the trunk.” In a subsequent work, following other writers, he refers this power to the agency of the tail, and even thinks that the animal may rise over obstacles in its course by the elevatory action of that organ. The tail is of considerable length, and according to some writers its extremity has a slight prehensile action which is of assistance to the animal in climbing. The membranes, when not in use, as when the Colugo is walking or climbing, fall in great folds at the sides of the body.

Passing now, by a natural transition, from the parachute-like membranes to the limbs which traverse and serve to extend them, we find that these exhibit certain peculiarities of structure which are amongst the anomalies of this singular creature. The bones of both fore and hind limbs are elongated and slender—a character which contrasts strongly with the general state of things in the Insectivora—and the ulna, which is particularly slender, is united to the radius towards the extremity. The feet consist of five digits, and they are specially adapted to enable the animal to climb readily upon the bark of the trunks and branches of trees. In the hind feet especially part of the tarsal bones (the navicular and cuboides) are constructed so that they can easily turn upon the astragalus and calcaneum, and thus the sole is turned inwards, an arrangement which facilitates the clasping action of the feet. The inner digits in all the feet possess considerable power of independent motion, although they are never converted into opposable thumbs; and this arrangement, combined with the presence of sharp strong claws upon all the toes, must greatly favour the peculiar mode of life of the animal. It is to be remarked that the structure of the hind feet presents some analogy to that prevailing in Bats, and that in repose the Colugo suspends itself from a branch bythe fore and hind feet, with the body and head hanging downwards, which is also a habit somewhat reminding us of the Chiroptera.

The head in theGaleopithecusis tolerably broad and a little flattened; the eyes are placed more laterally than in the Lemurs, and the orbits containing them form a bony ring which is interrupted behind.

HIND FOOT OF COLUGO.BONES OF HIND FOOT OF COLUGO.LOWER INCISORS OF COLUGO.

HIND FOOT OF COLUGO.

BONES OF HIND FOOT OF COLUGO.

LOWER INCISORS OF COLUGO.

The teeth are very peculiar. In the upper jaw there are on each side two incisors, those of one side separated from those of the other by a very wide space. The foremost of these incisors on each side has a single root and a notched crown; the hinder one is pointed and implanted by two roots. The canine which follows also possesses two roots; and this is followed by a molar series of five teeth, each inserted into the maxillary bone by three roots, and having a crown with three, four, or five cusps. In the lower jaw, which has the condyle curiously produced outwards, we find again on each side a series of five molar teeth, and in front of these a long canine with two roots; but the whole fore part of the jaw is occupied by six single-fanged incisors; the crowns of these are nearly horizontal, broad, flat, and notched, the notching of the two middle pairs being so deep as to form a regular comb. This structure is exceedingly remarkable, and occurs in no other animals, the nearest approach to it being the slightly pectinated teeth in the Desmodont Bats.

The teats in theGaleopithecusare situated on the sides of the breast, in the neighbourhood of the armpits. There is a pair on each side, placed close together, and on the same level. The female produces only a single young one at a birth, and the little creature, described by Mr. Wallace as at first very small, blind, and naked, clings closely to the breast of the mother, which is quite bare and very much wrinkled. Mr. Wallace sees in this adaptation of the region of the teats to the wants of an exceedingly incomplete offspring, some trace of a remote relation to the peculiarities of the Marsupials. The stomach in this curious animal is of considerable size; and the intestine is furnished with sacculated cæcum as long as the stomach.

COLUGO.

The Colugo varies considerably in colour, but is usually of an olive, brown, or blackish colour, mottled with whitish spots and blotches, which are said by Mr. Wallace to give it a resemblance to the colour of mottled bark, sufficient to render it difficult of observation. The lower surface of the body and membrane is of a tawny grey colour, and the whole of the fur which clothes the body and membranes is, although short, most exquisitely soft in texture. The length of the animal is about eighteen or twenty inches.

SKULL OF COLUGO.

The brain in theGaleopithecusis very small, and Mr. Wallace found it to possess such a remarkable tenacity of life that it was killed with difficulty by any ordinary means. He describes itas sluggish in its habits, at least during the day, when it generally rests clinging to the trunks of trees, and at this time, if it has occasion to move, it goes up the tree by short runs of a few feet, and then stops a moment as if it found the action difficult and fatiguing. We have already quoted Mr. Wallace’s description of the flight of the animal as witnessed by him early in the evening, and no doubt it is active enough during the dark hours.

The regular food of the Colugo appears to consist of vegetable substances, but authors differ somewhat in their statements upon this subject. By most zoologists it is said to feed on fruits; but Mr. Wallace says that “like the cuscus of the Moluccas, theGaleopithecusfeeds chiefly on leaves.” From the statements of some naturalists it would seem that it occasionally or habitually adds insects to its diet, and also that it frequently captures and devours small birds. In all probability the truth is that it eats almost anything that comes in its way.

Some five or six supposed species ofGaleopithecushave been described by various authors, but most of these are now admitted to be founded upon young animals, or upon mere varieties. The Colugo of the Philippine Islands is, however, generally regarded as a distinct species, although even as to this there is some doubt. It was described by Mr. Waterhouse asGaleopithecus philippinensis, and presents a close general resemblance to the species above described, but is smaller, has a shorter head, and shows certain slight differences in the teeth.

The preceding family, as already stated, is regarded by Mr. Gill as constituting an actual sub-order of Insectivora, and we have seen that its characters are really of a very singular kind. The remainder of the order is treated by him as forming a single great group, characterised by the absence of parachute membranes, the shortness and robustness of the limbs, and by the want of that peculiar comb-like structure of the incisor teeth which distinguishes theGaleopithecifrom all other Mammals. Moreover the condylar process of the lower jaw is never extended outwards. This group Mr. Gill proposes to nameBestiæorInsectivora vera.

The Bangsrings, or Sinsrings, form the first family, called Tupaiidæ, from the name of the most characteristic and best known genusTupaia, which again was derived by its discoverer and first describer, Sir Stamford Raffles, from the native name for a Squirrel, with which these animals are confounded by the Malays of Sumatra. The Bangsrings have either four or six incisors in the upper, and always six in the lower jaw; and three or four premolars, and four true molars on each side in both jaws. The canines are situated far back, and have a single root. In the skull the orbit is usually complete, or nearly so, and there is a complete zygomatic arch, with a small slit or aperture beneath the orbit. The bones of the shank are separate; the intestine has a large cæcum; and the feet are furnished with five toes, armed with strongly curved claws. The upper molar teeth are formed of two nearly equal parts, anterior and posterior, each of which represents a triangular prism narrowed inwards.

The Bangsrings live in and about trees, where their activity and general appearance give them a considerable resemblance to small Squirrels or Lemurs. They also remind one considerably of some of the smaller Marsupials. Their fur is exceedingly fine and soft; their tail generally long and well-clothed with hair (except inHylomys); and their food consists partly of fruits and partly of insects. The species inhabit South-eastern Asia and the islands of the Eastern Archipelago.

DENTITION OF FERRUGINOUS BANGSRING.

In the genusTupaia(orCladobates) from which the present family takes its name, there are four small incisor teeth separated from each other in the upper jaw; and six incisors, the middle four of which are close together, long, and much inclined forwards in the lower jaw. The upper canines are atsome distance from the hindmost incisors, the lower ones close to them (seefigure). Behind the canines there are on each side in both jaws three premolars, which increase in size backwards. These are followed by three true molars. The bony orbit is a complete ring, and the zygomatic arch is also complete, but perforated by an elongated aperture. The ears are of moderate size, and rounded; the eyes large and prominent; and the tail long, and well clothed with hair throughout its whole length; in fact in most species it is a bushy organ like that of many Squirrels.

In the Tana (Tupaia tana) the arrangement of the hair on the tail in two rows, something after the fashion of the barbs of a feather on the shaft, which is more or less recognisable throughout this genus, is especially remarkable; and as the hair is very long, the tail is rendered particularly bushy. This animal is one of the larger species, the body measuring from eight to nine inches in length, and its colour is rather variable, although usually exhibiting various shades of reddish-brown, becoming darker or blackish on the hinder part of the back, where, moreover, the greater part of the hairs are of uniform tint and not grizzled. The colour of the tail appears to be especially liable to vary—thus, according to Dr. Günther, in the ordinary form of the species the tail is black above, with the basal half of each hair rusty brown, and dark brown below; in another variety, described by Wagner as a distinct species under the name ofT. speciosa, the tail is brownish-red above, and bright rusty-red below; whilst in the beautiful form from which our illustration is taken the whole organ is of a reddish golden-yellow colour. This is Dr. Günther’s variety,chrysura(golden tail).

TANA—GOLDEN-TAILED VARIETY. (From theProceedings of the Zoological Society.)

The Tana is an inhabitant of the forests of Sumatra and Borneo. According to Sir Stamford Raffles, the animal is known to the country people of Sumatra under the name ofTupai tana, and he was informed that it was always found on or near the ground. A nearly allied but much smaller species (T. splendidulaof Dr. Gray) occurs with it in the last-named island; and another larger one (T. nicobarica) is found in the Nicobar Islands.

This species, theTupai Pressof the Malays of Sumatra, and theKekkesof the Sundanese in Java, is more widely distributed than the preceding, being found not only in the two islands above mentioned, but also in Borneo, Penang, and Singapore. It was first described by Sir Stamford Raffles. It is one of the larger species, the head and body measuring about eight inches, and the tail being fully of equal length. The colour of its fur is almost entirely a rusty red, becoming darker, however, on the tail and the hinder part of the back, where the hairs are more or less grizzled with white. The tail is not so bushy as that of the Tana. The aperture under the orbits is of an elongated oval form.

Sir Stamford Raffles, in his original account of this animal, describes it as being very lively and playful in its habits, and as feeding on fruits. He first saw it tame in the house of a gentleman in Penang, and states that this individual “was suffered to go about in perfect liberty, ranged in freedom over the whole house, and never failed to present himself on the breakfast and dinner table, where he partook of fruit and milk.” Dr. Cantor, in his “Catalogue of the Mammalia inhabiting the Malayan Peninsula and Islands,” gives the following interesting account of this Bangsring:—“The young of this very numerous species in hilly jungle,” he says, “is easily found, and becomes familiar with its feeder, though towards strangers it retains its original mistrust, which, in mature age, is scarcely reclaimable. In a state of nature it lives singly or in pairs, fiercely attacking intruders of its own species. When several are confined together, they fight each other, or jointly attack and destroy the weakest. The natural food is mixed insectivorous and frugivorous. In confinement individuals may be fed exclusively on either, though preference is evinced for insects; and eggs, fish, and earth-worms are equally relished. A short, peculiar, tremulous whistling sound, often heard by calls and answers in the Malayan jungle, marks their pleasurable emotions; as, for instance, on the appearance of food; while the contrary is expressed by shrill protracted cries. Their disposition is very restless, and their great agility enables them to perform the most extraordinary bounds in all directions, in which exercise they spend the day, till night sends them to sleep in their rudely-constructed lairs in the highest branches of trees. At times they will sit on their haunches, holding their food between the fore-legs; and after feeding they smooth the head and face with both fore-paws, and lick the lips and palms. They are also fond of water, both to drink and to bathe in. The female usually produces one young.” Dr. Cantor also states that “the lateral raised lines of the palms and soles, the posterior part of the first phalanges and the third phalanx, which is widened into a small soft disc, in fact, all the points which rest on the ground, are studded with little transversely-curved ridges, or duplications, similar to those observed under the toes of some Geckotidæ [Wall-Lizards], which fully accounts for the precision with which these animals perform the most astounding leaps from below, barely touching with their soles thepoint d’appuiabove. In a cage,” he adds, “theTupaiawill continue for hours vaulting from below, back downwards, poise itself for an instant, continuing back downwards under the horizontal roof, and regain the point of starting, and thus describe a circle, the diameter of which may be three or four times the length of the animal, in far shorter time than is required for the description.”

Allied to the Ferruginous Bangsring, and of nearly the same size, are two species which must be referred to on account of their geographical distribution, which carries this type of animals much farther to the west than we should expect. These are Elliot’s Bangsring (T. Ellioti), a species with unusually short and harsh fur, specimens of which have been obtained from Madras, Bengal, and Bombay; and Belanger’s Bangsring (T. Belangeri), originally procured in Pegu, but which also occurs in Burmah and Sikkim.

Horsfield’s Bangsring (Tupaia javanica) is a smaller animal than the preceding, an adult specimen measuring only about thirteen inches long, of which about one-half goes to the tail. The colour of its fur is greyish-brown, grizzled on the back, and with a whitish line on each shoulder. It inhabits Borneo, Sumatra, Java, and Arracan. The Little Bangsring (T. minor) is a still smaller species, measuring only five inches and one-third in length of body, but closely resembling the preceding in its characters. It is described by Dr. Günther from Bornean specimens. The Murine Bangsring (T. murina), which forms the genusDendrogaleof the late Dr. Gray, has also only beenfound in Borneo. It is a small species allied to the preceding, but has the tail more rat-like, and clothed only with comparatively short hairs, those of the lower surface especially being very short.

Besides the true Bangsrings forming the genusTupaia, this family includes two other small animals, one of which, Low’s Ptilocerque, is a very elegant little creature. The specimen originally described by Dr. Gray in 1848 was captured by Mr. Low in Rajah Brooke’s house in Borneo. It has a rather shorter head than the true Bangsrings, but its dentition is nearly the same; the aperture under the orbit is round, and the circle of the bony orbit is not quite complete behind. The most distinctive character of the animal is, however, to be found in its tail, which is an exceedingly peculiar organ. The tail itself is long and slender, and instead of being thickly clothed with bushy hairs, as in the Bangsrings, it has the basal portion hairy; then a long piece naked, covered with rings of broad, square scales, among which there are only a few short, scattered hairs; and, finally, about a third of its length is furnished with long hairs arranged on the two sides of the tail, so as to produce the appearance of the two wings of a dart or arrow (seefigure, p. 342).

The Ptilocerque, which is an inhabitant of Borneo and Sarawak, is between five and six inches long, with a tail rather longer than the body. Its general colour is blackish-brown above, minutely grizzled by the yellowish tips of the hairs; the lower parts and the cheeks are yellowish, and there is a black streak on each side of the face, enclosing the eyes. The tail is black, with the long hairs of the tip white, except a few towards the base. The habits of the animal are probably the same as those of the Tupaias.

A curious little animal belonging to this family was discovered in Sumatra by Dr. S. Müller. It has its muzzle produced into a long, movable snout, and the tail very short and naked. The skull is flatter than in the true Bangsrings; the orbit is incomplete; the sub-orbital aperture is in the form of a little fissure; and the dentition is different, there being six incisors in the upper as well as in the lower jaw, and four premolars on each side in both jaws. The total number of teeth is thus forty-four instead of thirty-eight. This animal has been found in Java and Sumatra.

The same, or a very nearly allied species, has been obtained in Pegu, and described by Mr. Blyth under the name ofHylomys peguensis. Professor Gill regards these animals as most nearly related toGymnurain the family Erinaceidæ.

SOLE OF RIGHTHIND FOOT OFELEPHANT SHREW.

Some curious little creatures, peculiar to Africa and its islands, in which, as in the Jerboas and Kangaroos, the hind legs are more developed than the fore limbs, enabling the animals to advance in a biped fashion by a succession of leaps, are regarded by most zoologists as nearly related to the Bangsrings; in fact, both Professor Mivart and Mr. Gill make these two families form a distinct tribe of Insectivora. They both have the same kind of molar teeth, and the intestine furnished with a large cæcum. But whilst the Bangsrings are squirrel-like animals, with feet adapted for a life in trees, the Jumping Shrews are mouse-like creatures, of terrestrial jumping habits, and furnished with a long, thin, proboscis-like muzzle, which has procured for them the name of Elephant Shrews. They have large eyes, and ears of a moderate size and rather widely separated; their hind limbs are considerably elongated, especially the shank and the metatarsus, or portion forming the foot, which has a naked sole that is applied to the ground; the two bones of the shank (tibia and fibula), and in general those of the forearm (radius and ulna), are attached to each other at the lower end; and the first or inner toe is either placed further back than the others, or altogether deficient. The sides of the muzzle are usually furnished with very long whiskers. The tail is long, and more or less rat-like, but covered with short hairs.

In two of the three genera into which the family is divided the number of teeth is forty, namely,on each side, incisors,33, canines,11, premolars,33, and molars,33, the incisors being small, and the upper canines furnished with two roots. In the exceptional genusRhynchocyon, which includes only a single species, there is only one incisor in the upper jaw, and even this falls out as the animal grows old.

The species of this family are peculiar to Africa, where they are found in Algeria and Barbary, along the east coast, and at the Cape of Good Hope.

This appears to be the commonest species in Southern Africa, where its habits were observed by the late Sir Andrew Smith, who founded for it the genusMacroscelides. It is about five inches long, with a tail of about three inches, and its colour is a tawny brown, becoming whitish on the limbs. It is diurnal in its habits, and very active, hunting for its insect prey among the scanty herbage and stunted shrubs, which alone flourish in the dry rocky spots which it chooses for its place of habitation. It resides in burrows in the ground, and when disturbed immediately rushes to take shelter in its home, or under some neighbouring rock or stone.

ELEPHANT SHREW.

Sir Andrew Smith described several other South African species, and at least one has been obtained on the Mozambique coast. In their structure and general habits they agree with the above-mentioned animal.

Besides these southern species, however, the French naturalists have discovered a species of this genus in Algeria, and it is also found to inhabit Barbary. It is known to the French colonists in Algeria by the name of the “Rat à trompe.” This animal is of the same size as the preceding—that is to say, about five inches long; its tail measures four inches, and its long slender snout about half an inch. It has a soft tawny fur on the back and sides, and the lower surface is whitish. The Algerian Jumping Shrew is said to feed not only upon insects, but also upon vegetable matters. It is gentle and inoffensive, and may be easily tamed, when its gambols are said to be very sprightly and amusing.

The Mozambique coast produces another species of this family, agreeing with those just noticed in nearly all its characters, but of much larger size, and further distinguished from them by having only four toes on each hind foot. The first toe, which is pushed far back, and considerably reduced in size in the Elephant Shrews, is entirely deficient in the Petrodrome.

While theMacroscelidesgenerally live in the plains, among grass and under bushes, the Petrodrome, as its name implies, prefers localities among the hills, where cavities and fissures in the rocks furnish it with a secure refuge. In three places where Professor Peters found it, this was the case. It lives on insects. In captivity it soon becomes familiar, although at first shy, but never inclined to bite. The natives at Tette call itSâro.

SOLE OF RIGHTHIND FOOT OFPETRODROME.

Besides the species ofMacroscelidesalready mentioned, and the Petrodrome, the coast of Mozambique has another animal which is referred to this family, although it presents several characters which separate it very decidedly from all the rest. It was first described by Professor Peters under the name ofRhynchocyon, which means “beaked dog,” although it must be confessed that there is nothing very dog-like about it. The name is in allusion to the large size of the canine teeth.

The Rhynchocyon, which is a very rare animal in collections, appears from the description and figure of Professor Peters to be a queer-looking beast. It measures about eight inches in length, exclusive of the tail, which is rather long, tapering, and rat-like, being covered with a ringed skin, and furnished with only a few scattered hairs. The muzzle is produced into a very long movable snout. The fur is of a rusty-brown colour, with a blackish tinge about the ears and the back of the head, and some light reddish spots on the hinder part of the back.

This animal, which is calledMutâuby the natives, lives in holes in the ground, from which itissues at night in search of the insects on which it feeds, and is chiefly interesting to the zoologist for the structural characters which it presents. Thus, whilst agreeing with the ordinary members of the present family sufficiently to warrant its being classified with them, and to prevent its going anywhere else, it differs from them in some exceedingly important particulars, which might almost justify its being placed in a family by itself. Although the hind legs are more developed than the fore limbs, the disproportion between them is hardly so great as in the true Jumping Shrews; and further, all the feet are reduced to the same four-toed condition as the hind feet in the Petrodrome, and the outer toe is shorter than the rest. But it is in the dentition that the anomaly is the greatest. The Rhynchocyon never has more than one small incisor tooth on each side in the upper jaw, and even this drops out as the creature advances in age; and the upper canine is a simple tooth with a single root. In the lower jaw there are three incisors on each side, and in both jaws the canines are followed by three premolars and three molars. In the hind legs the two shank-bones are united near the extremity as in the preceding species, but the two bones of the fore-arm (radius and ulna) are separate.

RHYNCHOCYON.

We pass now from groups of insect-eating animals the members of which must be sought in far distant countries, to a family represented in England by a very well-known species. Our Common Hedgehog, in fact, may serve as an excellent example of the family to which it belongs, although this certainly includes one species which presents rather anomalous characters.

All the Erinaceidæ have the two molar teeth broad, as in the preceding families; in fact, here the hinder ones are nearly square, and the tubercles forming their upper surface are rounded in form. The skull has a complete zygomatic arch, and the tympanic bone forms a bubble-like swelling on each side of the back of the skull. The back is clothed with hairs, among which there are a number of strong spines or bristles. The legs are short, and formed exclusively for walking, and the hind legs have the two bones of the shank (tibia and fibula) united. The intestine has no cæcum.

These animals are confined to the Old World, in nearly all parts of which some of the species are to be found. They feed chiefly upon insects and other small animals; most of them have the power of rolling themselves up into a ball, when the prickles with which the back is armed constitute a most formidable defensive armour; and in cold countries they pass the winter in a state of torpidity. Several fossil species have been found in Tertiary deposits in Europe.

Our Common English Hedgehog may serve as the type of this family; all the species of which, with only a single exception, belong to the same genus, and present a very close resemblance to each other, both in appearance and habits. All the Hedgehogs, in fact, are small animals of robust form, with very short tails, and the greater part of the hairs of the upper surface converted into sharp spines. The muzzle is conical, and the jaws contain thirty-six teeth, twenty of which are in the upper and sixteen in the lower jaw (see figure,p. 343). The arrangement of these teeth is peculiar. There are three incisors on each side, of which the inner one is considerably larger than the rest, and in the upper jaw these are separated by a small space from the next tooth, which is generally regarded as a premolar, in which case the animals have no canines. Behind this, in the upper jaw, are three premolars, gradually increasing in size until the third has very much the appearance of a true molar, but furnished with a cutting edge; and then three molar teeth, two of which are large and broad, nearly square, and crowned with very strong tubercles, admirably adapted for crushing the hard skins of the insects on which the Hedgehogs principally feed. The hindmost molar is a small tooth. In the lower jaw the innermost incisor is very large, and projects almost horizontally forward, and it is followed by three small teeth, the nature of which has been a matter of dispute. Two of them, however, are generally considered to be incisors, and the third a premolar, but by M. F. Cuvier they were all described as premolars, making, with another and larger tooth which follows them, four premolars in the lower as in the upper jaw, This last premolar is a carnassial or cutting tooth, corresponding to that in the upperjaw. It is separated by a small space from the last of the smaller anterior teeth, and is followed by three true molars, two of which are large, and furnished with four or five sharp tubercles, while the third is small, and shows only one strong point.

In the Common Hedgehog, as in most species of the genusErinaceus, the feet are all composed of five toes; the legs are short, so that the animal runs along with its belly nearly touching the ground; the spines, with which the whole upper surface is covered, are hard, sharp, round, about an inch in length, of a dirty-white colour, with a dark-brown or nearly black ring a little above the middle; the nose is black, and the unspined parts of the body are clothed with coarse yellowish-white hair. The ears are small and rounded. The total length of the adult Hedgehog is usually about ten inches.

Back to Index Next