28 
The large proportion of scandont species should be noted, as evidence 
that it is on niechanioal grounds, rather tlian from danger oi* desiccation, 
that the rain forest epiphytes are not conspicuous for huge fronds. 
Scandent plants increase the opportunity for a firm attachment at least 
as rapidly as they do the number of fronds. Xunierous species climb 
in a moderate way, like LinJmya MerrilU and Asplcmum einphylicum, 
both notable climbers in their high forest neighborhood; among these 
moderate climbers in the rain forest are Nephrodium 1112, Arthrop- 
teris ohliterata, Lindsaya scandens, AspJenium scandens, Scolopendrium, 
Polypodium papillosum^ etc. SteiiocJdaena. Lomagramma and Thayeria 
are most luxuriant climbers but the two former retain a limited ground 
connection for a long time or even permanently. 
All the peculiar ecological types found among the high forest epiphytes 
recur in the rain forest. Polypodium papillosum retains its fronds on 
the rare occasions when they dry and curl up, in spite of the fact that 
its stipe is jointed. This is probably true of MicroUpia hirsiita, also, 
but I have never seen it dry. There are also epiphytes in tlie rain forest 
which are not coriaceous^ do not normally dry out, and which have not 
+ 
articulate stipes. Among these, Foly podium^ pediculatum is notable 
because of its genus. Plants of this character do not occur in the high 
forest. In the rain and mossy forests they are never very large and are 
found where mossy trunks insure the constancy of the otherwise rarely 
interrupted humidity. 
A most interesting inhabitant of these mossy trunks is Monogramma 
trichoidea, in form perhaps the most hygrophytrc of all ferns. Its fine, 
scaly stems are woven into a network, along which are the very numerous 
"fronds," making a closer and finer tuft than mosses- often do. The 
single fronds are pendent, 3 to 7 centimeters long, and diamond-shaped 
in section. The longer diameter, 0.33 millimeter, is morphologically 
horizontal; the shorter, 0.25 millimeter, vertical. The very slender, 
fibro-vascular bundle is axial, surrounded on all sides by 1 to 2 layers 
of mesophyll. The four surfaces are exactly alike, stomata scattered 
over all, the epidermal cells rich in chlorophyll, with occasional Jdioblasts 
0.35 millimeter long, the outer half of the lumen of which is obliterated. 
In northern N"egros, where the rain forest descends to near' the sea level, 
I have found the shorter and slightly stouter M. darececarpa. 
The tree-top vegetation is still richer and less known than in the high 
forest. Together with several of the species already listed from the 
high forest, I have found in rain forest windfalls Vittaria alternans, 
V. minor, Polypodium {GoniopKlehimn) subauriculatum , P. Beddomei, 
P. (Selliguea) caudiforme, and a sterile ElapJioglossum, With these are 
a great Nepenthes, Melastomatacem and Gesneriacece, The trees most in 
evidence are Quercus, with huge AgatJtis on the higher rid^-es. 
Floristically it is to be noted that Eu-Polypodium and its offshoot 
