32 
probably of use in this way to many smaller foms. Cartilaginous bor- 
ders, if sharp or deflexed, also help to keep the uetlier surface dry. Their 
greatest development in Philippine ferns is in ElapJioglossum, 
Bemoval of «*fl/^r.— The ready removal of water from the frond is 
insured and facilitated in a variety of ways. One of these is by a smooth, 
even, Avaxy, unwettable surface, as in Asphnium miisae folium (the cuticle 
of which is firm enough to be stripped off), A. PhijlJituIis, and Ptcris 
opaca. 
Caudate tips are a very familiar structure serving this end and, of 
course, acuminate tips in general are more common and less conspicuous 
structures of the same kind. Among conspicuously caudate tips are 
those of Oleandra colithrina, Coniogramme fraxinea, C. serrulata, 2 cen- 
timeters long^ AspJenhim miisaefoUiim, A. PhyUittdis, Antrophijum lati- 
folium, A. semicostatum and Polypodium papillosum. Long-acuminate, 
rather than caudate, are those of Bipteris, Nephrolepis laurifolia, Asph- 
nium vulcanicum, A, caudaium, A. a/fine (the pinnae), Scolopendrium 
scliizocarpum, StenocMaeha, Blechnum egrcgium, AntropJiyiim planta- 
gineum, Prosaptia^ Polypodium subauriculatumy P. Zippelii, P. incnr- 
vaium, F. ritymatodes and all its relatives, Drynnrla and all its relatives, 
Lomagramma and CJieiropIeuria. Yery nearly all of these are epiphytes. 
The removal of water from an erect fern is brought about in the same 
wslj by an attenuate base, like that of Dipteris, Syngramma, Meniscium, 
Polypodium sinuosum and CheiropAeuriu. Essentially like these are 
plants such as Odontosoria with cuneate, erect pinnules. Pinnae drawn 
down at the base, instead of attached horizontally will drain in the same 
way; illustrations are Lindsaya Havicei and Asplenium caudatum and 
other species. The reduction of the basiscopic half of the pinna has 
the same effect, the part of the lamina which is removed being that 
^ 
portion which could not readily drain down the rachis; this modification 
is begun in Asphnium vulcanicum; carried farther in A. tcncnnn and its 
relatives and in Polystichum; farther still in Asphnium resectum; and 
completed in our dimidiate Lindsay as and Adiantum. 
If detracted pinnse are carried farther they become decurrent, forming 
a wing on the rachis and stipe which serves at once as a drain for water 
and mechanically, aside from any value it may have in increasing the 
leaf-area. Microlepia pinnata and Calliptcris escuhnta show slightly 
decurrent pinnse. Winged rachises and stipes are exceedingly common; 
they are illustrated by Aspidium^ decurrenSj Stenosemia pinnata (upper 
part), Davallla decurrens, Diplazium Williamsi, Schizostege pacliysora, 
Polypodium dolichopiermn, P. affine, P. Schneideri, and Lecanopteris, 
A broad wing is sometimes convex upward on both sides, effecting a 
depression along the axis, as in P. papillosum, P. Sclineideri and P. 
heraclcum, the pinn^ of Phris longifolia and the whole frond of Poly- 
podium caudlforme. The fine divisions of Onychium are concave above. 
