OF CEYLON AND INDIA. 
377 
which arises one fruit, standing upon an erect axis emerging 
from the boat-shaped spathe, which is split along the upper 
side and usually lies nearly prostrate upon the rock. The 
fruit is ribbed, and is usually open, with the lai’ger 
valve persistent upon the stalk, while the smaller has fallen 
off with the seeds. In specimens taken below the water, as 
in PI. XXVIll., or in the upper right-hand figure of 
PI. XXXI., the secondary shoots can be seen as little buds, 
prostrate on the thallus ; those close to the tip are still often 
in the leafy vegetative condition. 
Germination and Life History . — I have only been able to 
get two or three seedlings of this plant, at Hatton in Ceylon, 
and all were at the age of the one figured in PI. XXXII., fig. 
1. Evidently the germination takes place much as in Dicræa 
stylosafucoides, giving rise to a short stout hypocotyledonary 
axis with a few leaves at the top on a condensed epicotyle- 
donary stem, the leaves arranged according to some 
phyllotaxy which I have not been able to discover, but not 
at any rate distichous. At the base of the seedling the thallus 
emerges, and soon widens out at the tip and begins to branch. 
The branching is more fully shown in fig. 2 ; at first it is 
usually alternate, but later it is not infrequently sub-opposite, 
as the photographs show. The growing apex is like that of 
Dicræa, or like that of H. olivaceum described below 
(excepting that it is an apex, and not a margin, as in the 
latter), with a collenchymatous cap. The branching is close 
to the apex, exogenous, and lateral as in Podostemon 
subulatus, with a secondary shoot formed between the two 
lobes in each case, at a very early period. Vascular bundles 
are also developed leading to the branches of the thallus and 
to the secondary shoots. The thallus grows rapidly in size, 
and may reach a length of several inches during even the com- 
paratively short vegetative period available in the Bombay 
Ghats. The lateral branches themselves branch again, the 
first branchlet being on the basiscopic side as usual. The 
secondary shoots are like those of Dicræa, mere tufts of small 
leaves emerging from little openings in the thallus. 
