334 MR. H. N. RIDLEY ON THE GENUS BROMHEADIA. 
parallel case occurs in Liparis, where the terrestrials usually have 
softer leaves withering on the stems, the epiphytes having arti- 
culated ones. Pfitzer (‘ Morphologische Studien’) has separated 
the genus into two mainly on this ground. In the epiphytic 
species the rhizome is more branched and the masses attain a 
larger size. This is certainly due to the smaller amount of com- 
petition upon the lofty trees where the epiphytes grow. Another 
noticeable point is in the shortening of the stem. The terrestrial 
species attain a height of six feet in damp localities, and there 
are oftener branches in the inflorescence, so that it partakes more 
of the nature of a panicle. The shortening is most conspicuous 
in Bromheadia aporoides, where the inflorescence appears as a tuft 
of brown bracts, almost eapitulous, but even then showing signs of 
branching at the base. The elongate stems of B. palustris and 
B. sylvestris are doubtless brought about by competition with 
the surrounding herbage, besides the dampness of the lower 
stratum of air which increases the vegetative activity. There is 
no competition upon the lofty trees where the epiphytes grow, 
and in all probability the air is drier. The strong wind which 
often must buffet the epiphytes, too, would probably cause much 
damage to long straggling plants like the terrestrial ones. 
B. alticola has the leaves distinctly bilobed, as is very common 
in other epiphytes. This has almost entirely disappeared in 
B. palustris. 
The leaves of B. aporoides are laterally flattened, stiff, recurved, 
and pungent, very much like those of some Dendrobium, but less 
succulent. This plant was growing on the tree with the stems 
at right angles to the trunk, so that the edges of the leaves 
would have been turned up to the light had the plant had them 
flattened in the normal manner, which is perhaps the reason for 
their being laterally flattened. 
The two epiphytes and B. palustris are real sun-loving plants. 
They grow exposed to the full blaze of the sun, and the flowers 
of all are somewhat similarly coloured ; the prevailing colour is 
white, somewhat greenish in B. aporoides. The two others are 
visited by a species of Xylocopa which is very abundant in Sin- 
gapore, and nests both in stumps and old timber on the ground 
and in the dead branches of taller trees, often very high up. The 
bee is certainly not particular as to the colouring of the flowers 
it visits; but the white flowers of these two species are very 
showy and conspicuous. White flowers are fairly abundant ın 
