416 LAMARCK, HIS LIFE AND WORK 
tantin, Bonnier, and others, all demonstrating that 
the environment acts directly on the plant. 
Henslow also suggests that endogens have origi- 
nated from exogenous plants through self-adaptation 
to an aquatic habit,* which is in line with our idea 
that certain classes of animals have diverged from the 
more primitive ones by change of habit, although this 
has led to the development of new class-characteris- 
tics by use and disuse, phenomena which naturally do 
not operate in plants, owing to their fixed conditions, 
Other botanists—French, German, and English— 
have also been led to believe in’ the*directiniluence 
of the mzlzeu, or environment. Such are Viet,t+ and 
Scott Elliot,{ who attributes the growth of bulbs to 
the “" direct influence of the climate.” 
In a recent work Costantin§ shares the belief em- 
phatically held by some German botanists in the 
direct influence of the environment not only as modi- 
fying the form, but also as impressing, without the 
aid of natural selection, that form on the species or 
part of its inherited stock; and one chapter is de- 
voted to an attempt to establish the thesis that 
acquired characters are inherited. 
**° A Theoretical Origin of Endogens from Exogens through 
Self-Adaptation to an Aquatic Habit,” Zznnean Society Journal: 
Botany, 1892, /. ¢., xxix., pp. 485-528. A case analogous to kineto- 
genesis in animals is his statement based on mathematical calcula- 
tions by Mr. Hiern, ‘‘ that the best form of the margin of floating 
leaves for resisting the strains due to running water is circular, or at 
least the several portions of the margin would be circular arcs” (p. 
G7): 
+‘* De l’'Influence du Milieu sur la Structure anatomique des 
Végétaux,” Ann. Sct. Nat. Bot., ser. 6, xii., 1881, p. 167. 
{ ‘‘ Notes on the Regional Distribution of the Cape Flora,” 7vans- 
actions Botanical Society, Edinburgh, 1891, p. 241. 
S$ Les Végétaux et les Milieux cosmigues, Paris, 1898, pp. 292. 
