224 Yapp . — Two Malayan * Myrmecophilous' Ferns . 
Mention has been made of the fact that Blume figured two 
species of Lecanopteris , though he only described one. The 
differences between the figures of these two species seem to 
lie chiefly in the respective shapes of the leaf-segments. 
Those of L. carnosa are represented as comparatively wide, 
and tapering to the acuminate apex, those of L. pumila as 
narrower, and rounded at the apex. 
Lecanopteris pumila is not represented in the Kew Her- 
barium, while there are seven sheets of specimens identified 
as L . carnosa. Of these four are from Perak, one from the 
Philippines, and two from the Malay Archipelago. The 
plants from these several localities differ from each other in 
the size and shape of the leaf-segments. Those from the 
Malay Islands correspond to Blume’s type figure of L. car- 
nosa , that from the Philippines forms a type by itself, while 
those from Perak bear considerable resemblance to Blume’s 
figure of L. pumila. In the absence of more complete material, 
it is difficult to decide whether L. pumila can be maintained 
as a species or not, but in view of the great variability of the 
leaf-lamina in many Ferns, it would seem likely that these 
three forms may be nothing more than local varieties of 
L. carnosa. For the present therefore, it will be best to leave 
the Perak specimens (including those from Gunong Inas) 
under the name of Polypodium ( Lecanopteris ) carnosum ; 
though, if P. (. Lecanopteris ) pumilum (Blume) should ulti- 
mately be found to be a distinct species, they would in all 
probability belong to it rather than to P. carnosum. 
Summary. 
1. Polypodium carnosum and P. sinuosum are two Malayan 
epiphytes, whose thick fleshy rhizomes are tunnelled by a 
system of galleries, similar to those of Myrmecodia and 
Hydnophytum , and, like them, invariably inhabited by ants. 
2. In both Ferns a tissue consisting of large cells with thin 
walls and no intercellular spaces is formed in certain definite 
areas near the apex of the stem. This tissue breaks down at 
