662 
as is the case with the moss Taxithelium instratum, or on bowlders in 
the streams where the mosses Fissidens zollingeri, F. zippelianus, and 
Ectropothecium and others are found. In the low altitudes, filmy ferns 
of the genus J'richomanes are encountered only on shady, damp rocks 
at the edges of the streams; however, as one ascends their beds, the 
rocks become more and more covered with mosses; but in such situations, 
because of the swift currents in times of high water, the type is poorly 
represented. On the whole, the infrequency of these plants in the low- 
lands and indeed below the Hugenia-Vaccinium formation, is a note- 
worthy fact and is in direct response to the dry conditions during a 
portion of the year which favor what for convenience may be called 
annual rather than daily tropophytes. In the ridge under consideration, 
and below 1,000 meters, the filmy fern vegetation is scanty and it ap- 
pears only in the shade; above this altitude it becomes abundant and 
it then increases with the elevation, however being always more abun- 
dant in the shady rather than in the sunny spots. Mymenophyllum 
multifidum, H. smithii, Trichomanes pallidum, T. bipunctatum, and 
others are among the species present. (See Pl. XXXVIII.) On the 
other hand, the liverworts and mosses are prominent features between 
Plots A and D, although they are much more so from F to H. Indeed, 
in these latter places, trees are covered with these plants from the bases 
of their trunks to the ends of their twigs, where the leaves are usually 
grouped. On rocks, fallen trees or limbs, and in every place in the 
shade where the wash from the heavy rains does not prevent their 
occurrence, dense masses, which give such an aspect to the vegetation 
called the “mossy forest,” accumulate. Plates XXXVI, XXXVI, and 
X XXVIII show the richness of this forest in these epiphytes, and the 
list of mosses and liverworts given below indicate the number of species 
which occur although, no doubt, only a small percentage of the total 
number has been collected: Hepaticee: Brazzania erosa, B. praerupta, 
Lepidoza trichodes, Mastigophora diclados, Schistochila aligera, Pru- 
llania integristipula, and F’. orientalis. Musci: Dicranoloma blumei, 
Leucobryum sanctum, L. javense, L. angustifolium, Macromitrium cus- 
pidatum, M. reinwardtii, Rhizogonium spiniforme, Spiridens reinwardtit, 
Aerobryum lanosum, and Sematophyllum altopungens. 
The third group of epiphytes is largely composed of ferns.” Many 
of these are facultative epiphytes and frequently the moss and liverworts 
furnish a substratum for them. Since this substratum is alternately 
dry and wet, the response to the severe conditions is found in their 
© Dr. E. B. Copeland, who is writing on the comparative ecology of the 
Philippine ferns, informs me that epiphytic ferns which are not embedded in 
moss usually have their roots covered with a felty mass of persistent root hairs, 
and that these are often absent when the roots are so embedded. Such ferns 
would then have special absorptive organs and would be classified with the 
orchids and liverworts. 
oo... 
