[491] The reader may also refer for further information on the subject of malformed pears to Irmisch. 'Flora,' 1858, p. 38, tab. i; Lindley, 'Theory of Horticulture'; Caspary, 'Bull. Soc. Bot. France,' vol. vi, 1859 (Rev. Bibl.), p. 235; Duhamel, 'Phys. Arbr.,' liv. iii, cap. 3. p. 393, fig. 308; Bonnet, 'Recherch. Us. feuilles,' tab. xxvi, fig. 2; Moquin-Tandon, 'El. Ter. Veg.,' p. 384, &c. Some of the cases recorded are, however, instances of true prolification. [492] 'Revue Horticole' 1868, p. 310. [493] The interest of this accident is great, as showing how an habitually superior ovary may become inferior--a change so rare in its occurrence that its existence has been denied, and thus forming a marked contrast with the frequency with which the converse change of an inferior ovary to a superior one, from want of union with the calyx or from imperfect development of the peduncle, may be observed. It is also interesting as showing how the peduncle may become swollen, and at the same time how the woody deposit of the endocarp may, as if by compensation, be deficient. And, again, the malformation is not without significance in regard to the relationship between the drupaceous and the pomaceous subdivisions of _Rosaceae_. The case would fitly be included under alterations of position, but the sheets relating to that subject were printed off before the publication of M. Carriere's notice. [494] 'Bull. Soc. Bot. France,' 1860, vol. vii, p. 881. [495] "Monstr. Veget.," in 'Neue Denkschrift.' [496] "Sched. de Monst. Plant." in 'Act. Helvet.,' t. ii, pl. ii, f. 14. [497] 'Bull. Soc. Bot. France,' vol. viii, 1861, p. 144. [498] 'Ann. Sc. Nat.,' ser. 2, t. i, p. 308, pl. ix _c_, fig. 1. [499] 'Bull. Soc. Bot. France,' 1862, t. ix, p. 37. [500] 'Consid. org. Fleur.,' Montpell., 1829, 25, 26, pl. ii, f. 18 and 19. [501] 'Bull. Bot.,' t. i, p. 7, tab. 1. [502] 'Linnaea,' vol. x, p. 604, tab. 5. [503] 'Mem. Acad. Sc. Toulouse,' 5 ser., vol. iii. [504] 'Re. nosol. Veget.,' pp. 342. [505] 'Illustr. Hortic.,' 1868, Misc., p. 62. [506] 'Ann. Soc. Linn.,' Paris, t. i, p. 139. [507] 'Mem. Acad. Toulouse,' t. 6, 1862. [508] 'D. C. Prod.,' ii, pp. 172, 187. [509] Richard, "Obs. sur les bulbilles des Crinum;" 'Ann. Sc. Nat.,' t. ii, p. 12. pl. i, fig. 1, 2. See also A. Braun, "Memoire sur les graines charnues des Amaryllidees," &c.; 'Ann. Sc. Nat.,' 1860, vol. xiv, p. 1, tab. 1. CHAPTER II. ELONGATION.