Chap. XIII. 



REVERSION. 



37 



body in the same individual animal. — In the eleventh chapter, 

 many cases of reversion by buds, independently of seminal 

 generation, were given — as when a leaf-bud on a variegated, 

 curled, or laciniated variety suddenly reassumes its proper 

 character ; or as when a Provence-rose appears on a moss-rose, 

 or a peach on a nectarine-tree. In some of these cases only 

 half the flower or fruit, or a smaller segment, or mere stripes, 

 reassumed their former character; and here we have with buds 

 reversion by segments. Vilmorin 20 has also recorded several 

 cases with plants derived from seed, of flowers reverting by 

 stripes or blotches to their primitive colours : he states that in all 

 such cases a white or pale-coloured variety must first be formed, 

 and, when this is propagated for a length of time by seed, striped 

 seedlings occasionally make their appearance; and these can 

 afterwards by care be multiplied by seed. 



The stripes and segments just referred to are not due, as far 

 as is known, to reversion to characters derived from a cross, 

 but to characters lost by variation. These cases, however, as 

 Naudin 21 insists in his discussion on disjunction of character, are 

 closely analogous with those given in the eleventh chapter, in 

 which crossed plants are known to have produced half-and-half 

 or striped flowers and fruit, or distinct kinds of flowers on the 

 same root resembling the two parent-forms. Many piebald 

 animals probably come under this same head. Such cases, 

 as we shall see in the chapter on Crossing, apparently result 

 from certain characters not readily blending together, and, as 

 a consequence of this incapacity for fusion, the offspring either 

 perfectly resemble one of their two parents, or resemble one 

 parent in one part and the other parent in another part; 

 or whilst young are intermediate in character, but with ad- 

 vancing age revert wholly or by segments to either parent- 

 form, or to both. Thus young trees of the Cytisus adami are 

 intermediate in foliage and flowers between the two parent- 

 forms; but when older the buds continually revert either 

 partially or wholly to both forms. The cases given in the 

 eleventh chapter on the changes which occurred during growth 



20 Verlot, ' Des Varie'te's,' 1865, p. 63. 



21 ' Nouvelles Archives du Museum ' 

 torn. i. p. 25. Alex. Braun (in bis 



'Rejuvenescence,' Eay Soc, 1853, p. 

 315) apparently holds a similar 

 opinion. 



