OF CEYLON AND INDIA. 
35] 
which are usually considerably stretched by the growth 
of the outermost bracts and the flower. Many specific 
characterizations have been chiefly based on differences 
in the form of the tips of the bracts, while in reality these 
differences simply express different stages of the process 
above explained, and until it is complete it is not safe 
to base any diagnosis on the form of the tip or keel of the 
bracts. 
As mentioned in the preceding paper, several species have 
been made from the Paikara material, the separation char- 
acters chosen being chiefly the length and number of the 
bracts ; D. Wightii, for instance, depends for its character 
simply on the fact of its having been taken from deeper 
water, before the long tips of the leaves had fallen. I 
examined all the plants I could at Paikara, and came to the 
conclusion that the forms mentioned could not be regarded 
as anything but phases. 
The flower of this species is very similar In all points to 
that of D. elongata, and the fruit is the same, but with 
broader dehiscence ribs (PI. XX., fig. 10). 
Rejuvenescence by the formation of new growing points 
on broken or resubmerged thalli appears to take place to a 
considerable extent. 
The herbarium material of D. dichotoma is on the whole 
good, apart from the confusion caused over the development 
of the bracts, which has led to its being divided into many 
species. 
Dicræa WaiSichii, Tul. 
(Plates XX.-XXI.) 
As explained in the preceding paper, I include Weddell’s 
D. pterophylla in this species, it having been separated from 
it simply on account of misconception of the process of bract 
development ; Weddell examined spirit material collected 
by Sir J. D. Hooker, while Tulasne and Griffith used dry 
material, in which the keel \vas more disintegrated. I divide 
the species into two varieties : of the second, D. Wallichii 
