Chap. XVIII. CONTABESCENCE. 165 



plants if the roots had grown out of the hole at the bottom. In some few 

 cases, however, as with Digitalis, transplantation did not prevent fertilisa- 

 tion ; and according to the testimony of Mawz, Brassica rapa, when pulled 

 up by its roots and placed in water, ripened its seed. Flower-stems of 

 several monocotyledonous plants when cut off and placed in water likewise 

 produce seed. But in these cases I presume that the flowers had been 

 already fertilised, for Herbert 83 found with the Crocus that the plants 

 might be removed or mutilated after the act of fertilisation, and would 

 still perfect their seeds; but that, if transplanted before being fertilised, 

 the application of pollen was powerless. 



Plants which have been long cultivated can generally endure with 

 undiminished fertility various and great changes ; but not in most cases 

 so great a change of climate as domesticated animals. It is remarkable 

 that many plants under these circumstances are so much affected that the 

 proportions and the nature of their chemical ingredients are modified, 

 yet their fertility is unimpaired. Thus, as Dr. Falconer informs me, 

 there is a great difference in the character of the fibre in hemp, in the 

 quantity of oil in the seed of the Linum, in the proportion of narcotin to 

 morphine in the poppy, in gluten to starch in wheat, when these plants 

 are cultivated on the plains and on the mountains of India ; nevertheless, 

 they all remain fully fertile. 



Oontabescence. — G-artner has designated by this term a peculiar condition 

 of the anthers in certain plants, in which they are shrivelled, or become 

 brown and tough, and contain no good pollen. When in this state they 

 exactly resemble the anthers of the most sterile hybrids. Gartner, 84 in his 

 discussion on this subject, has shown that plants of many orders are occa- 

 sionally thus affected; but the Caryophyllaceas and Liliaceaa suffer most, 

 and to these orders, I think, the Ericaceae may be added. Contabescence 

 varies in degree, but on the same plant all the flowers are generally 

 affected to nearly the same extent. The anthers are affected at a very 

 early period in the flower-bud, and remain in the same state (with one 

 recorded exception) during the life of the plant. The affection cannot be 

 cured by any change of treatment, and is propagated by layers, cuttings, 

 &c, and perhaps even by seed. In contabescent plants the female organs 

 are seldom affected, or merely become precocious in their development 

 The cause of this affection is doubtful, and is different in different cases 

 Until I read Gartner's discussion I attributed it, as apparently did Herbert' 

 to the unnatural treatment of the plants; but its permanence under 

 changed conditions, and the female organs not being affected, seem incom- 

 patible with this view. The fact of several endemic plants becoming 

 contabescent m our gardens seems, at first sight, equally incompatible 

 with this view ; but Kolreuter believes that this is the result of their trans- 

 plantation. The contabescent plants of Dianthus and Verbascum, found 

 wild by Wiegmann, grew on a dry and sterile bank. The fact that exotic 



J 'journal of Hort. Soc.,' vol. ii. ung/ s. 10, 121 ; 'Dritte Fortsetzung,' s . 



M.n-*- tt , ■ - . 57, He *ert, 'Amaryllidaceae,' p. 355. 



« Beitrage zur Kenntm< & c ., s . Wiegmann, 'Ueber die Bastarderzeu- 

 117 et seq. ; Kolreuter, Zweite Fortsetz- gung,' s. 27. 



