672 UNDERWOOD: FERNS OF THE PHILIPPINES 
FAMILY 5. CYATHEACEAE 
The tree-ferns of the Philippines do not appear to have been 
-adequately collected, but the same is true of the family everywhere. 
They are not a suitable subject for ordinary herbarium study and 
should be specially prepared as already noted above. The char- 
acteristic armature or vestiture of the leafstalks should always be 
secured and if possible a section of the caudex. The genera 
represented in the Philippines are as follows : 
1. Sori marginal; indusium coriaceous, 2-valved ; herbaceous species. CIBOTIUM. 
Sori dorsal ; tree-ferns. 2. 
2. Indusium inferior, cup-shaped. CYATHEA. 
Indusium inferior, half cup-shaped. HEMITELIA. 
Indusium wanting. ALSOPHILA. 
Cibotium is represented by C. Barometz,* often cultivated in 
American conservatories, and is not a tree-fern. The other genera 
form the genuine tree-ferns and include thirteen known species, 
four in Cyathea, eight in A/sophila and a single Hemitelia. 
FamIty 6, PoLyPODIACEAE 
The true ferns are the most abundant of any family and form 
three fourths of the fern flora of the islands, which is their 
usual proportion. The number of genera is so large that we can 
best distinguish them in their tribal relations separately : 
I. Sporangia scattered over the under surface of the leaf-blade in a uniform layer.} 2. 
Sporangia dorsal or marginal, accumulated in definite sori. 3- 
2. Leaves of two sorts; a shield-like basal leaf attached to the surface of the sub- 
stratum and a furcate spreading one with localized sporangial surfaces. 
1. Alcicornieae.t 
Leaves approximately uniform ; sporangia covering entire leaves or pinnae. 
2. Acrosticheae. 
3. Sori marginal, continuous or interrupted, covered by a more or less modified portion 
of the leaf-margin. + 3. Pterideae. 
Sori dorsal, or at most submarginal, with or without indusia. _ 
aise ree Ria Arle AP vs Bhs MS ’ <ccaiaiaeailiiilainget iON 
* Included under Dicksonia in Synopsis Filicum. 
+ Certain Dryopterideae with confluent sori may be sought here. Cf / olybotryas 
Anapausia, E-genolfia, etc. Their habit is distinctively aspidioid, and lacks the 
jointed leaf-stalks of the Acrosticheae, : 
t We propose this tribal name for the ‘ stag-horn ferns,’’ believing their umque 
habit should separate them from the Acrosticheae with which they have usually been 
associated. The name comes from A/cicornium Gaud. (1826), which is an older 
name than Platycerium. 
t The indusium is wanting in Votholaena. 
