through Self-adaptation to a Moist or Aquatic Habit . 721 
restrial species have acquired sufficient adaptations to maintain an aerial 
existence. 
The degeneracy of Monocotyledons is seen in every organ, as e. g. in 
the exhausting process of flowering and seeding. Thus bulbs, so character¬ 
istic of certain orders, which throw up a central flowering stem, perish with 
the completion of the reproductive process. Larger plants, as Agave and 
Aloe , die in the same manner. Lastly, Palms sometimes follow suit. 
Thus is it with Corypha umbraculifera, the Talipot Palm of Ceylon and 
Southern India. It has enormous leaves, a single blade, it is said, being 
large enough to cover a whole family. In about seventy years it is then 
able to flower; but the entire tree perishes immediately after the effort has 
been made. 1 
Miss Sargant observes that: 4 The reduction in structure so character¬ 
istic of aquatic species is very strongly marked in their young seedlings. 
. . . Ancestral features have commonly disappeared or become obscure 
in the general loss of differentiation. Thus, the fact that terminal leaves 
seem characteristic of aquatic embryos suggests very strongly that their 
peculiar position is due rather to siippression of the axis than to any 
reminiscence of a stemless period in the history of the race.’ 2 
‘ Considerable reduction of structure commonly occurs in the embryo 
and seedling of aquatic and semi-aquatic plants’ 3 [my itals.]. 
The above quotations apply as well to Monocotyledons generally. 
Miss Sargant elsewhere notices how ‘ the petiolar tube of cohering 
cotyledons is accompanied by a thickening, or at least much shortened 
hypocotyl’, and adds that it is ‘ commonly very short in Monocotyledons 
the thickening leading to bulbs, corms, &c. This is what might be antici¬ 
pated from the subsequent tufted condition of the leaves of so many of that 
class, as well as in perennial dicotyledonous hygrophytes and hydrophytes, 
in which not only the primary internode or hypocotyl, but the subsequent 
ones are suppressed. 
Miss Sargant calls attention to the prevalence of tufted or ‘squat’ 
plants on the Alps, and attributes it to the short hot summer following 
the melting of the snows. Insolation, however, may assist in arresting 
the axis. In South Africa, she adds, ‘ parallel conditions are seen in the 
dry season being followed by the heavy rains of the wet one.’ 4 
The following British plants will remind the reader of this correlation 
between tufted foliage, arising from perennial axial structures, and an 
aquatic habit. Many Grasses, Rushes, and Sedges, Iris, Eriocatdon , Isoetes , 
Narthecium, Toffieldia , Stratiotes, Alisma, Sparganium , Hydrochar is, Lit - 
1 Gardeners’ Chronicle, vol. xlvii, p. 426, and Supplementary Illustration. 
3 Reconstruction of a Race of Primitive Angiosperms. Ann. of Bot., xxii, p. 151. 
3 Ibid., p. 152. 
Theory of Otigin of Monocotyledons, &c. Ann. of Bot., vol. xvii, p. 79. 
