FOOTNOTES:

Fig.196.—Increased number of carpels, tulip.

Fig.197.—Fruit of St. Valery apple cut lengthwise.

Pleiotaxy of the gynœcium.—An increase in the number of whorls of which the pistil consists is not of very frequent occurrence. Generally after the formation of the whorl of carpels, the energy of the growing point ceases, or if by chance it be continued, the result is more generally the production of a new flower-bud (median prolification) than the repetition of the carpellary series. It is necessary also to distinguish between the veritable augmentation of the pistil and the semblance of it, brought about by the substitution of carpels for some other organs, as pistillody of the stamens, and even of the segments of the perianth, is not very unfrequent, as has already been stated under the head of substitution. Again, the increased number of carpels which is sometimes met with in such flowers, asMagnoliaorDelphinium, where the ovaries are arrangedin spiral series, is not strictly referable to the present category.

The orange is one of the plants most frequently subject to an augmentation in the number of carpellary whorls; sometimes this is due to the stamens assuming the guise of carpels, but at other times the increase occurs without any alteration in the stamens or other organs. If the adventitious carpels be exposed, they are covered with yellow rind, while those portions that are covered by the primary carpels are destitute of rind. Some varieties of the double tulip are very subject to a similar change, but, in this case, the petals and the stamens very frequently become more or less carpellary in their nature. Fig. 196 represents an increased number of whorls of carpels in the variety called "rex rubrorum," the segments of the perianth having been removed.

In the St. Valery apple, already referred to, there is a second whorl of carpels above the first, a fact which has been made use of to explain the similar structure of the pomegranate.

The tomato (Lycopersicum esculentum) is another plant in which an adventitious series is frequently produced, and generally in combination with the primary series.

In the Chinese primrose (Primula sinensis) a supernumerary whorl is frequently met with, generally associated with other changes in the construction and arrangement of the parts of the flower.

M. de Candolle[455]mentions a flower ofGentiana purpureawith four carpels in one series, and five others in the circle immediately above them. Wigand[456]alludes to an instance wherein there was a second pair of carpels above the first inVinca herbacea. Dr. Sankey has forwarded flowers of aPelargoniumhaving a double series of carpels, eight in the outer row, five in the inner, and this condition is stated to exist in the flowersof the same plant for two years consecutively. InAquilegiaI have met with a similar increase in the whorls of carpels.[457]Meissner records a similar augmentation inPolygonum orientale.[458]

Wigand[459]describes and figures a flower ofVinca minor, in which there were two carpels intervening between the ordinary pair, and a similar illustration has been observed by the writer inAllamanda cathartica. Eichler[460]has put on record a similar case in a capparid.

Marchand[461]mentions a polycarpellary berberid (Epimedium Musschianum). The supernumerary carpels in this flower were placed on a short axis, which originated in the axils of the stamens, and as these latter organs were present in their usual number and position, the adventitious carpels could not be considered as resulting from a transformation, or substitution of carpels for stamens.

Lastly, the instance cited by Dr. Allman[462]inSaxifraga Geummay be alluded to. Here there was a row of adventitious carpels between the stamens and pistils, the backs of the carpels being turned towards the axis of the flowers. Dr. Allman explains the presence of the supernumerary parts by the supposed production of a whorl of secondary axes between the stamens and the centre of the flower. These axes are further supposed to bear imperfect flowers, of which the additional carpels are the only traces, but this explanation seems forced.

In addition to the references already cited the following may be given:

Duchartre, 'Ann. Sc. Nat.,' 4 ser., vii, p. 23 (Tulip).Ferrari, 'Hesperides,' pp. 271, 395, 405. Duchartre, 'Ann. Sc. Nat.,'4 ser., 1844, vol. i, p. 294. Maout, 'Leçons Elément.,' vol. ii, pp. 488–9. Clos, 'Ann. Sc. Nat.,' 1865, p. 317 (Citrus Aurantium).Clos, 'Bull. Soc. Bot. Fr.,' vol. xiii; 'Rev. Bibl.,' p. 75. Pasquale, 'Reddicont Accad. Sc. Fis. e Math. Napoli.' Octr. 1866 (Solanum Lycopersicum).

Duchartre, 'Ann. Sc. Nat.,' 4 ser., vii, p. 23 (Tulip).

Ferrari, 'Hesperides,' pp. 271, 395, 405. Duchartre, 'Ann. Sc. Nat.,'4 ser., 1844, vol. i, p. 294. Maout, 'Leçons Elément.,' vol. ii, pp. 488–9. Clos, 'Ann. Sc. Nat.,' 1865, p. 317 (Citrus Aurantium).

Clos, 'Bull. Soc. Bot. Fr.,' vol. xiii; 'Rev. Bibl.,' p. 75. Pasquale, 'Reddicont Accad. Sc. Fis. e Math. Napoli.' Octr. 1866 (Solanum Lycopersicum).

On the general subject of multiplication, in addition to previous citations, the reader may be referred to A. P. de Candolle, 'Théorie Elément. Bot.,' ed. 3, p. 89.

Increased number of flowers in an inflorescence.—This happens generally as a result of over luxuriant growth, and scarcely demands notice here, being rather referable to variation than to malformation. The increased number of florets in the spikelets of some grasses has already been alluded to (p. 351). Thus spikelets of wheat occasionally produce more than the three florets which are proper to them.[463]It will be remembered that in this as in many other grasses there are rudimentary florets, and it is no matter for surprise that these florets should occasionally be fully developed.

FOOTNOTES:[392]'Bull. Soc. Bot. Fr.,' vol. vii, 1860, p. 587.[393]'Fragment. Phyt. Austral.,' part xx, p. 270.[394]'Bull. Acad. Belg.,' xvi, pt. i, p. 60, "Fuchsia," p. 125, c. ic.[395]"Théorie de la feuille," 'Arch. des Sciences Bibl. Univers.,' 1868.[396]See Engelmann, 'De Antholysi,' p. 16, section 12.[397]Verhandl. des Botanisch. Vereins Brandenburg,' 1859, 1 heft.[398]See Henslow. 'Mag. Nat, Hist.' 1832, vol. v, p. 429.[399]'Phytologist,' September, 1857.[400]Seemann's 'Journal of Botany,' iv, p. 168, t. 47, f. 3.[401]'Illust. Hortic.,' 1866, misc., p. 97.[402]See Fresenius, 'Mus. Senkenb.,' bd. 2, p. 43. Schlechtendal, 'Bot. Zeit.,' iv, pp. 403, 492,Veronica tetrandra.[403]'Flora,' 1865, tab. 6, fig. 8.[404]'Org. Veget.,' t. i, p. 497, pl. 42, f. 3.[405]'El. Ter. Veg.,' p. 354.[406]Cited in "Rev. Bibl." of 'Bull. Soc. Bot. Fr.,' 1866, p. 171.[407]Loc. cit., 351.[408]'Mém. Acad. Toulous.,' vi, 1862, ex 'Bull. Soc. Bot. Fr.,' "Rev. Bibl.," vol. ix, 1862. p. 127.[409]'Flora.' 1857. p. 289.[410]L. c., p. 354.[411]Giraud, 'Ed. Phil. Mag.,' Dec., 1839.[412]SeeCerasus Caproniana, D. C. 'Plant. Rar. Hort. Genev.,' tab. 18.[413]Nees, 'Linnæa,' v, p. 679, tab. 11 (Schœnodorus).[414]'Gard. Chron.,' 1852, p. 452.[415]See Cramer, 'Bildungsabweich.' pp. 16, 24.[416]'Linnæa,' 1842, p. 389, c. ic.[417]Seemann's 'Journal of Botany,' 1867, vol. v, p. 158.[418]Cramer, 'Bildungsabweich,' p. 66,Astrantia major,Eryngium, to which may be addedDaucus,Heracleum, &c.[419]See also Reinwardt, 'Nov. Act. Acad. Nat. Cur.,' 12, 1, 37; and Masters, 'Journ. Linn. Soc.,' vi, p. 24.[420]'Organog. Veget.,' tab. 53.[421]'Missbild.,' p. 206.[422]Ehrenberg, 'Flora,' 1846, p. 704.[423]'Flora,' 1860, tab. 7.[424]'Ann. Sc. Nat.,' 3 ser., t. x, p. 207.[425]'Mem. Mus.,' xii. t. 17.[426]'Nov. Act. Acad. Nat. Cur.,' xv, tab. xxviii, f. 3; 'Bot. Mag.,' t. 1622. "Caryophyllus spicam frumenti referens." A similar malformation inDianthus barbatusis not uncommon. It has lately been introduced into gardens under the name ofDianthus"mousseux," but is not likely to find favour with gardeners.[427]'Bull. Soc. Bot. France,' t. vi, 1859. p. 268.[428]Weber, 'Verhandl. Nat. Hist. Vereins. Rhein. Pruss.,' 1860.[429]'Bot. Zeit.,' 1848, p. 217.[430]'De Anthol.,' p. 17, § 12.[431]'Linnæa,' vol. ii, 1827, p. 85.[432]'De Antholysi,' p. 17, tab. iii, f. 15, 16; Weinmann, 'Phytanth. iconogr.,' nro. 292.[433]See Hildebrand, 'Bot. Zeit.,' 1862, p. 209, tab. viii; Cramer, 'Bildungsabweich.,' p. 7, tab. xiii; Engelmann, 'De Antholysi,' p. 18, &c. For similar changes inGagea arvensissee Wirtgen, 'Flora,' 1838, t. xxi. p. 350, and 'Flora.' 1846, p. 353. Some of these are cases of synanthy.[434]Schlechtendal, 'Bot. Zeit.,' xx, 1862, p. 301.[435]'Phil. Bot.,' § 126.[436]C. Morren, 'Bull. Acad. Belg.,' xix, part ii, p. 17.[437]'Seemann's Journal of Botany,' iii, p. 354.[438]On this point the reader will find an excellent summary in Lindley's 'Vegetable Kingdom,' cd. iii, p. 183a, and in Darwin, 'Fertilisation of Orchids,' p. 292. See also Crüger,'Journ. Linn. Soc.,' t. viii, p. 134.[439]'Seemann's Journal of Botany,' vol. iv, p. 168, tab. 47.[440]Ibid., t. iv. 1866, p. 168, t. xlvii, f. 1.[441]'Bildungsabweich,' p. 8; see also 'Bot. Zeit.,' 1852, p. 425.[442]'Journ. Linn. Soc.,' t. ii, p. 104. tab. 1, fig.B.[443]Lindl., "Orchid. Ind.," 'Jour. Linn. Soc.,' iii, p. 9.[444]'Arch. Bot.,' ii, p. 300, tab. xvi, f. 11.[445]'Seemann's Journal of Botany,' v, p. 318, tab. lxxii, figs. A 4, 4a.[446]"Monstr. Veg.," in 'Neue Denkschrift,' p. 17, tab. vii.[447]'Flora,' t. viii, 1825, p. 736.[448]'Mem. Soc. d'Hist. Nat.,' ii, 1, p. 212, tab. iii.[449]'Bull. Soc. Bot. Fr.,' t. vii, 1860, p. 26.[450]'Beitr. Morphol. und Biol. Orchid.,' quoted by Cramer; 'Bildungsabweich,' p. 9.[451]Masters, 'Journ. Linn. Soc.,' viii, p. 207. See also Rodigas, 'Bull. Soc. Bot. Belg.,' iv, p. 266, for similar changes inCypripedium Hookeræ.[452]Kirschleger, 'Flora,' 1844, p. 131.[453]'Bildungsabweich,' p. 11, tab. xiv, f. 3.[454]'Bull. Acad. Roy. Belg.,' t. xix, part 2, p. 171.[455]'Organogr. Végét.,' t. i, p. 509, tab. 40, figs. 6, 7.[456]'Flora,' 1856, p. 715.[457]'Linn. Trans.,' t. xxiii, p. 364, tab. 34, fig. 5.[458]'Monog. Polygon,' pl. 3, K. f. 12.[459]'Flora,' 1856, tab. viii.[460]Ibid., 1865, tab. ix, f. 6.[461]'Adansonia,' vol. iv, 1864, p. 127.[462]'Ann. Nat. Hist.,' 1845, vol. xvi, p. 126.[463]See Schlechtendal, 'Bot. Zeit.,' t. xviii, p. 381 (Triticum); also 'Flora,' t. xiv, 1831, p. 5 (Avena).

[392]'Bull. Soc. Bot. Fr.,' vol. vii, 1860, p. 587.

[393]'Fragment. Phyt. Austral.,' part xx, p. 270.

[394]'Bull. Acad. Belg.,' xvi, pt. i, p. 60, "Fuchsia," p. 125, c. ic.

[395]"Théorie de la feuille," 'Arch. des Sciences Bibl. Univers.,' 1868.

[396]See Engelmann, 'De Antholysi,' p. 16, section 12.

[397]Verhandl. des Botanisch. Vereins Brandenburg,' 1859, 1 heft.

[398]See Henslow. 'Mag. Nat, Hist.' 1832, vol. v, p. 429.

[399]'Phytologist,' September, 1857.

[400]Seemann's 'Journal of Botany,' iv, p. 168, t. 47, f. 3.

[401]'Illust. Hortic.,' 1866, misc., p. 97.

[402]See Fresenius, 'Mus. Senkenb.,' bd. 2, p. 43. Schlechtendal, 'Bot. Zeit.,' iv, pp. 403, 492,Veronica tetrandra.

[403]'Flora,' 1865, tab. 6, fig. 8.

[404]'Org. Veget.,' t. i, p. 497, pl. 42, f. 3.

[405]'El. Ter. Veg.,' p. 354.

[406]Cited in "Rev. Bibl." of 'Bull. Soc. Bot. Fr.,' 1866, p. 171.

[407]Loc. cit., 351.

[408]'Mém. Acad. Toulous.,' vi, 1862, ex 'Bull. Soc. Bot. Fr.,' "Rev. Bibl.," vol. ix, 1862. p. 127.

[409]'Flora.' 1857. p. 289.

[410]L. c., p. 354.

[411]Giraud, 'Ed. Phil. Mag.,' Dec., 1839.

[412]SeeCerasus Caproniana, D. C. 'Plant. Rar. Hort. Genev.,' tab. 18.

[413]Nees, 'Linnæa,' v, p. 679, tab. 11 (Schœnodorus).

[414]'Gard. Chron.,' 1852, p. 452.

[415]See Cramer, 'Bildungsabweich.' pp. 16, 24.

[416]'Linnæa,' 1842, p. 389, c. ic.

[417]Seemann's 'Journal of Botany,' 1867, vol. v, p. 158.

[418]Cramer, 'Bildungsabweich,' p. 66,Astrantia major,Eryngium, to which may be addedDaucus,Heracleum, &c.

[419]See also Reinwardt, 'Nov. Act. Acad. Nat. Cur.,' 12, 1, 37; and Masters, 'Journ. Linn. Soc.,' vi, p. 24.

[420]'Organog. Veget.,' tab. 53.

[421]'Missbild.,' p. 206.

[422]Ehrenberg, 'Flora,' 1846, p. 704.

[423]'Flora,' 1860, tab. 7.

[424]'Ann. Sc. Nat.,' 3 ser., t. x, p. 207.

[425]'Mem. Mus.,' xii. t. 17.

[426]'Nov. Act. Acad. Nat. Cur.,' xv, tab. xxviii, f. 3; 'Bot. Mag.,' t. 1622. "Caryophyllus spicam frumenti referens." A similar malformation inDianthus barbatusis not uncommon. It has lately been introduced into gardens under the name ofDianthus"mousseux," but is not likely to find favour with gardeners.

[427]'Bull. Soc. Bot. France,' t. vi, 1859. p. 268.

[428]Weber, 'Verhandl. Nat. Hist. Vereins. Rhein. Pruss.,' 1860.

[429]'Bot. Zeit.,' 1848, p. 217.

[430]'De Anthol.,' p. 17, § 12.

[431]'Linnæa,' vol. ii, 1827, p. 85.

[432]'De Antholysi,' p. 17, tab. iii, f. 15, 16; Weinmann, 'Phytanth. iconogr.,' nro. 292.

[433]See Hildebrand, 'Bot. Zeit.,' 1862, p. 209, tab. viii; Cramer, 'Bildungsabweich.,' p. 7, tab. xiii; Engelmann, 'De Antholysi,' p. 18, &c. For similar changes inGagea arvensissee Wirtgen, 'Flora,' 1838, t. xxi. p. 350, and 'Flora.' 1846, p. 353. Some of these are cases of synanthy.

[434]Schlechtendal, 'Bot. Zeit.,' xx, 1862, p. 301.

[435]'Phil. Bot.,' § 126.

[436]C. Morren, 'Bull. Acad. Belg.,' xix, part ii, p. 17.

[437]'Seemann's Journal of Botany,' iii, p. 354.

[438]On this point the reader will find an excellent summary in Lindley's 'Vegetable Kingdom,' cd. iii, p. 183a, and in Darwin, 'Fertilisation of Orchids,' p. 292. See also Crüger,'Journ. Linn. Soc.,' t. viii, p. 134.

[439]'Seemann's Journal of Botany,' vol. iv, p. 168, tab. 47.

[440]Ibid., t. iv. 1866, p. 168, t. xlvii, f. 1.

[441]'Bildungsabweich,' p. 8; see also 'Bot. Zeit.,' 1852, p. 425.

[442]'Journ. Linn. Soc.,' t. ii, p. 104. tab. 1, fig.B.

[443]Lindl., "Orchid. Ind.," 'Jour. Linn. Soc.,' iii, p. 9.

[444]'Arch. Bot.,' ii, p. 300, tab. xvi, f. 11.

[445]'Seemann's Journal of Botany,' v, p. 318, tab. lxxii, figs. A 4, 4a.

[446]"Monstr. Veg.," in 'Neue Denkschrift,' p. 17, tab. vii.

[447]'Flora,' t. viii, 1825, p. 736.

[448]'Mem. Soc. d'Hist. Nat.,' ii, 1, p. 212, tab. iii.

[449]'Bull. Soc. Bot. Fr.,' t. vii, 1860, p. 26.

[450]'Beitr. Morphol. und Biol. Orchid.,' quoted by Cramer; 'Bildungsabweich,' p. 9.

[451]Masters, 'Journ. Linn. Soc.,' viii, p. 207. See also Rodigas, 'Bull. Soc. Bot. Belg.,' iv, p. 266, for similar changes inCypripedium Hookeræ.

[452]Kirschleger, 'Flora,' 1844, p. 131.

[453]'Bildungsabweich,' p. 11, tab. xiv, f. 3.

[454]'Bull. Acad. Roy. Belg.,' t. xix, part 2, p. 171.

[455]'Organogr. Végét.,' t. i, p. 509, tab. 40, figs. 6, 7.

[456]'Flora,' 1856, p. 715.

[457]'Linn. Trans.,' t. xxiii, p. 364, tab. 34, fig. 5.

[458]'Monog. Polygon,' pl. 3, K. f. 12.

[459]'Flora,' 1856, tab. viii.

[460]Ibid., 1865, tab. ix, f. 6.

[461]'Adansonia,' vol. iv, 1864, p. 127.

[462]'Ann. Nat. Hist.,' 1845, vol. xvi, p. 126.

[463]See Schlechtendal, 'Bot. Zeit.,' t. xviii, p. 381 (Triticum); also 'Flora,' t. xiv, 1831, p. 5 (Avena).

A diminution in the number of parts is generally due to suppression, using that word as the equivalent of non-development. It corresponds thus in meaning with theFehlschlagenof the Germans, theavortement complèteof Moquin and other French writers. It differs from atrophy, or partial abortion, inasmuch as the latter terms apply to instances wherein there has been a partial development, and in which evolution has gone on to a certain extent, but has, from some cause or other, been checked. These cases will be found under the head of diminished size of organs. As the word abortion is used by different authors in different ways, it is the more necessary to be as precise as possible in the application of the term. In the present work abortion is used to apply to cases wherein parts have been formed, but wherein growth has been arrested at a certain stage, and which, therefore, have either remainedin statu quo, while the surrounding parts have increased, or have, from pressure or other causes, actually diminished in size.

In practice, however, it is not always possible to discriminate between those instances in which there has been a true suppression, an absolute non-development of any particular organ, and those in which it has been formed, and has grown for a time, but has afterwards ceased to do so, and has been graduallyobliterated by the pressure exercised by the constantly increasing bulk of adjacent parts, or possibly has become incorporated with them. In the adult flower the appearances are the same, though the causes may have been different.

Absolute suppression of the main axis is tantamount to the non-existence of the plant, so that the terms "acaulescent," "acaulosia," etc, must be considered relatively only, and must be taken to signify an atrophied or diminished size of the stem, arising from the non-development of the internodes.

The absence of lateral branches or divisions of the axis is of frequent occurrence, and is dependent on such causes as the following:—deficient supply of nutriment, position against a wall or other obstacle, close crowding of individual plants, too great or too little light, too rich or too poor a soil, &c.

Probably the absence of the swollen portion below the flower in the case of many proliferous roses, double-flowered apples, as already referred to, may be dependent on the non-development of the extremity of the peduncle or flower-stalk. Thus, in a double-flowered apple recently examined, there was a sort of involucel of five perfect leaves, then five sepals surrounding an equal number of petals, numerous stamens, and five styles, but not a trace of an expanded axis, nor of any portion of the carpels, except the styles. The views taken as to the nature of this and similar malformations must depend on the opinion held as to the nature of inferior pistils, and on the share, if any, that the expanded axis takes in their production. As elsewhere said, theevidence furnished by teratology is conflicting, but there seems little or nothing to invalidate the notion that the end of the flower-stalk and the base of the calyx may, to a varying extent, in different cases, jointly be concerned in the formation of the so-called calyx-tube and of the inferior ovary. Obviously it is not proper to apply to all cases where there is an inferior ovary the same explanation as to how it is brought about.

As these pages are passing through the press, M. Casimir de Candolle has published a different explanation as to the nature of the hip of the rose, having been led to his opinion by the conclusion that he has arrived at, that the leaf is to be considered in the light of a flattened branch, whose upper or posterior surface is more or less completely atrophied.

According to M. de Candolle, the calyx-tube, in the case of the rose, is neither a whorl of leaves, nor a concave axis in the ordinary sense in which those terms are used, but is rather to be considered as a ring-like projection from an axis arrested in its ulterior development. The secondary projections from the original one correspond to an equal number of vascular bundles, and develope into the sepals, petals, stamens, and ovaries. If these organs remained in a rudimentary condition, the tube of the calyx would be reduced to the condition of a sheathing leaf. The rose flower, then, according to M. de Candolle, may be considered as a sheathing leaf, whose fibro-vascular system is complete, and from which all possible primary projections are developed.[464]

If, as M. de Candolle considers, the leaf and the branch differ merely in the fact that the vascular system is complete in the latter, and partly atrophied in the former, it would surely be better to consider the "calyx-tube" of the rose as a concave axis rather than as a leaf, seeing that he admits the fibro-vascular system to be complete in the case of the rose.

With reference to this point the reader is referred to Mr. Bentham's account of the morphology and homologies of theMyrtaceæin the 'Journal of the Linnean Society,' vol. x, p. 105. See alsoante, pp. 71, 77.

Some doubts also exist as to the nature of the beak or columella of such fruits as those ofGeraniaceæ,Malvaceæ,Umbelliferæ,Euphorbiaceæ, &c. The nature of the organ in question may probably be different in the several orders named; at any rate the subject cannot be discussed in this place, and it is mentioned here because, now and then, it happens that the organ in question is completely wanting, and hence affords an illustration of suppression.

FOOTNOTES:[464]'Théorie de la feuille.' p. 24.

[464]'Théorie de la feuille.' p. 24.

This subject may be considered, according as the separate leaves of the stem or of the flower are affected, and according as either the number of members of distinct whorls, or that of the whorls themselves, is diminished.

The terms aphylly, meiophylly, and meiotaxy may be employed, according as the individual leaves are altogether wanting, or with reference to the diminished number of parts in a whorl, or a decrease in the verticils.

Aphylly.—Entire suppression of the leaves is a rare phenomenon. Under ordinary circumstances it occurs in mostCactaceæ, in some of the succulent Euphorbias, and other similar plants, where the epidermal layers of the stem fulfil the functions of leaves. But even in these plants leaf-like organs are present in some stage or another of the plant's life.

Partial suppression of the leaf occurs sometimes in compound leaves, some or other of the leaflets of which are occasionally suppressed. Sometimes, as Moquin remarks, it is the terminal leaflet which is wanting, when the appearance is that ofCliffortia, at other times the lateral leaflets are deficient, as inCitrusorPhyllarthron.Ononis monophyllaandFragaria monophyllamay be cited as instances of the suppression of the lateral leaflets. If the blade of the leaf disappears entirely, we have then an analogous condition to that of the phyllodineous acacias.

With reference to the strawberry just mentioned, Duchesne, 'Hist. Nat. Frais.,' p. 133, says that this was a seedling raised from thefraisier des bois, and the characters of which were reproduced by seed, and have now become fixed. The monophyllous condition has been considered to be the result of fusion of two or more leaflets, but however true this may be in some cases, it is not the case with this strawberry. M. Paillot states that he has found the variety in a wild state.[465]

In like manner varieties of the following plants occur with simple leaves,Rosa berberifolia(Lowea),Rubus Idæus,Robinia pseudacacia,Fraxinus excelsior,Sambucus nigra,Juglans nigra, &c.

In one instance seen by the writer every portion of the leaf of a rose was deficient, except the stipules and a small portion of the petiole. (See abortion.)

Meiophylly.—A diminished number of leaves in a whorl occasionally takes place; thus, in some of theStellatæ, and frequently inParis quadrifolia, the number of leaves in the verticil is reduced. Care must be exercised in such instances that an apparent diminution arising from a fusion of two or more leaves be not confounded with suppression.

Meiophylly of the calyx or perianth.—A lessened numberof sepals is not a very common occurrence among dicotyledonous plants. Seringe figures a proliferous flower ofArabis alpinawith two sepals only, and a similar occurrence has been noticed inDiplotaxis tenuifolia.

InCattleya violaceathe writer has met with a flower in which the uppermost sepal was entirely wanting, while two of the lateral petals were fused together. Moquin records that in some of the flowers ofChenopodiaceæ, in which the inflorescence is dense, a suppression of two or three sepals sometimes occurs. The species mentioned areAmbrinaambrosioides,Chenopodium glaucum, andBlitum polymorphum.

Meiophylly of the corolla.—Suppression of one or more petals is of more frequent occurrence than the corresponding deficiency in the case of the sepals. AmongCaryophyllaceæimperfection as regards the numerical symmetry of the flower is not uncommon, as in species ofCerastium,Sagina,Dianthus, &c. InRanunculaceæthe petals are likewise not unfrequently partially or wholly suppressed. A familiar illustration of this is afforded byRanunculus auricomus, in which it is the exception to find the corolla perfect.[466]Some varieties ofCorchorus acutangulusin west tropical Africa are likewise subject to the same peculiarity. AmongstPapilionaceæabsence of the carina or of the alæ is not uncommon, as inTrifolium repens,Faba vulgaris, &c.

Moquin relates a case of the kind in the haricot bean, in which the carina was entirely absent, and another in the pea, where both carina and alæ were missing, thus reducing the flower to the condition that is normal inAmorphaandAfzelia. Suppression of the upper lip in such flowers asCalceolariahas been termed by Morren "apilary."

InOrchidaceæentire absence of the labellum, frequently without any other perceptible change, is of common occurrence. The writer has seen numerous specimens of the kind inOphrys apiferaandO. aranifera; also inDendrobium nobile,Ærides odoratum,Cypripedium villosum,Listera ovata, &c. Morren[467]mentions analogous deficiencies inZygopetalum maxillare,Calanthesp., andCattleya Forbesii. In most of these there was also a fusion of the two lower sepals, which were so twisted out of place as to occupy the situation usually held by the labellum. At the same time the column was partially atrophied. To this deficiency of the lip the author just quoted proposed to apply the term acheilary,α-χειλαριον. Mr. Moggridge has communicated to the author an account of certain flowers ofOphrys aranifera, in which the petals were deficient, sometimes completely, at other times one or two only were present.

Meiophylly of the andrœcium.—Suppression of one or more stamens, independently of like defects in other whorls, is not uncommon, even as a normal occurrence,e.g.inCarlemannia, where the flower, though regular, has only two stamens, and other similar deficiencies are common in Dilleniads.

Seringe relates the occurrence of suppression of some of the stamens inDiplotaxis tenuifolia,[468]St. Hilaire inCardamine hirsuta, others inC. sylvatica.

InCaryophyllaceæsuppression of one or more stamens has been observed inMollugo cerviana,Arenaria tetraquetra,Cerastium, &c.[469]Among violets the writer has observed numerous flowers in which two or three stamens were suppressed. Chatin[470]alludes to a similar reduction inTropæolum, while in flowers that are usually didynamous absence of two or more of the stamens is not unfrequent,e.g.inAntirrhinum,Digitalis,while in a flower ofCatalpaa solitary perfect stamen, and a complete absence of the sterile ones usually present, have been observed. This might have been anticipated from the frequent deficiencies in the staminal whorl in these plants under what are considered to be normal conditions. Reduction of the staminal whorl is also not unfrequent inTrifolium repensandT. hybridum, and has been seen inDelphinium, &c.[471]

Meiophylly of the gynœcium.—Numerical inequality in the case of the pistil, as compared with the other whorls of the flower, is of such common occurrence, under ordinary circumstances, that in some text-books it is looked on as the normal condition, and a flower which is isomerous in the outer whorls is by some writers not considered numerically irregular if the number of the carpels does not coincide with that of the other organs.

But in this place it is only necessary to allude to deviations from the number of carpels that are ordinarily found in the particular species under observation. As illustrations the following may be cited:—Arenaria tetraqueta, which has normally three styles, and a six-valved capsule, has been seen with two styles, and a four or five-valved capsule. Moquin relates an instance inPolygala vulgariswhere there was but a single carpel, a condition analogous to that which occurs normally in the allied genusMozinna.Reseda luteolaoccasionally occurs with two carpels only, while Aconites, Delphiniums, Nigellas, and Pæonies frequently experience a like diminution in their pistil.

In a flower ofPapaver Rhæasthe writer has recently met with an ovary with four stigmas and four parietal placentæ only, and to Mr. Worthington Smith he is indebted for sketches of crocus blooms with two, and in one instance only a solitary carpel.

Moquin cites the fruit of a wild bramble (Rubus)in which all the little drupes which go to make up the ordinary fruit were absent, except one, which thus resembled a small cherry. InCratægusthe pistil is similarly reduced to a single carpel, as inC. monogyna.

The writer has on more than one occasion met with walnuts (Juglans) with a single valve and a single suture.[472]If the ovary ofJuglansnormally consisted of two valvate carpels, the instances just alluded to might possibly be explained by the suppression of one carpel, but the ovary inJuglansis at first one-celled according to M. Casimir de Candolle.

Among monocotyledonsConvallaria majalismay be mentioned as very liable to suffer diminution in the number of its carpels, either separately or in association with other changes.[473]

Meiophylly of the flower as a whole.—In the preceding sections a reduction in the parts of each individual whorl has been considered without reference to similar diminution in neighbouring verticils. It more commonly happens, nevertheless, that a defect in one series is attended by a corresponding imperfection in adjoining ones. Thus trimerous fuchsias and tetramerous jasmines may frequently be met with, and Turpin describes a tetramerous flower ofCobæa scandens. Perhaps monocotyledonous plants are more subject to this numerical reduction of the parts of several verticils than are other flowering plants. Thus, in bothLilium lancifoliumandL. auratumthe writer has frequently met with pentamerous flowers. InConvallaria maialisa like deviation not unfrequently occurs.[474]M. Delavaud has recorded a similar occurrence in a tulip.[475]

Dimerous crocuses may also sometimes be met with. In one flower of this nature the segments of the perianth were arranged in decussating pairs, and thefour stamens were united by their filaments so as to form two pairs.

M. Fournier mentions something of the same kind in the flower of anIris.[476]

Orchids seem peculiarly liable to the decrease in the number of their floral organs. Prillieux[477]mentions a flower ofCattleya amethystinawherein each whorl of the perianth consisted of two opposite segments.

The same observer has put on record instances of a similar kind inEpidendrum Stamfordianum. In one flower of the last-named species the perianth consisted of one sepal only, and one lip-like petal placed opposite to it.[478]Morren[479]describes a flower ofCypripedium insigne, in which there were two sepals and two petals. Of a similar character was the flower found by Mr. J. A. Paine, and described in the following terms by Professor Asa Gray in the 'American Journal of Science,' July, 1866:—"The plant" (Cypripedium candidum) "bears two flowers: the axillary one is normal; the terminal one exhibits the following peculiarities. The lower part of the bract forms a sheath which encloses the ovary. The labellum is wanting; and there are two sterile stamens, the supernumerary one being opposite the other,i.e.on the side of the style where the labellum belongs. Accordingly the first impression would be that the labellum is here transformed into a sterile stamen. The latter, however, agrees with the normal sterile stamen in its insertion as well as in shape, being equally adnate to the base of the style. Moreover, the anteposed sepal is exactly like the other, has a good midrib and an entire point. As the two sterile stamens are anteposed to the two sepals, so are the two fertile stamens to the two petals, and the latter are adnate to the style a little higher than the former. The style is longer than usual, is straight and erect; the broad, disciform stigma thereforefaces upwards; it is oval and symmetrical, and a light groove across its middle shows it to be dimerous. The placentæ, accordingly, are only two. The groove on the stigma and the placentæ are in line with the fertile stamens.

Here, therefore, is a symmetrical and complete, regular, but dimerous orchideous flower, the first verticil of stamens not antheriferous, the second antheriferous, the carpels alternate with these; and here we have clear (and perhaps the first direct) demonstration that the orchideous type of flower has two stamineal verticils, as Brown always insisted."

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