308 WILLIS : MORPHOLOGY OP THE PODOSTEMACEÆ 
South India. The detailed description given below refers 
in general to the common Hakinda form, Gardner’s original 
type of the species, which I have described as L. zeylanica 
Gardneriana, but the points of difference and of interest 
found in the other forms are also described. 
Habitat . — The Ceylon forms of this species grow at 
elevations from 1,000 to 2,000 feet. It is found on smooth 
rocks in places where, during the vegetative season at least, 
the flow of water is very swift, but as a rule not in places 
where it is also very much broken. Most often the plants 
cover the rock to the exclusion of other species, but they 
are frequently mixed with Hydrobryum olivaceum, less 
often with Farmeria metzgerioides, and occasionally (usually 
at junctions of eddies with the main stream) with Podos- 
temon subulatus or Dicræa stylosa, var. fucoides, all of w^hich 
are also very dwarf forms, or forms which lie very low 
upon the rocks. The habitats of the Indian forms are, so 
far as I can judge from their dry season appearance, very 
similar. I have found them mixed in many places with 
Hydrobryum lichenoides, and some of Mr. Barber’s 
specimens are mixed with Griffithella Hookeriana. 
Dyy Season Appearance . — The plant is exposed to the air 
early in the year (e.^., I found it in flower at Hakinda on 
9th January, 1898, 8th January, 1899, and 17th December, 
1899), flowers as soon as exposed, and very quickly ripens 
and sheds its seeds. It is at this period that all the existing 
herbarium material has been collected. Large expanses of 
dry smooth rock, often many yards across, may be seen 
covered with a brown coating of thalli, thickly studded with 
ripe fruits, while close to the water’s edge may be seen 
flowers in all stages from opening bods to nearly ripe fruits. 
Several pieces of rock are shown in PL X. As a common 
rule there is little form or structure to be seen in a hasty 
glance, but often such a specimen as the large one there 
figured may be found, in which it is evident that the thallus 
is branched on a definite system, and is not a continuous 
