UNDERWOOD: FERNS OF THE PHILIPPINES 671 
FAMILY 2. CERATOPTERIDACEAE 
The aquatic Ceratopferis, apparently a tropical cosmopolite, is 
the only known representative of this family. 
FAMILY 3. SCHIZAEACEAE 
Four genera of this family have been found in the archipelago ; 
they may be distinguished as follows : 
I. Sporangia solitary, covered by scales, arranged on marginal teeth of the leaves ; 
leaves pinnate ; stems twining. LyGopIuM. 
Sporangia in distichous spikes; plants small, erect. 2. 
2. Leaves narrow, simple, grass-like. 3- 
Leaves broader, flabellately forked. LopHIpIuM. 
3- Spikes in a penicillate tuft. ACTINOSTACHYS, 
Spikes in a pinnate cluster. SCHIZAEA. 
The last three genera, which have usually been united under 
Schizaea,* are inconspicuous plants represented in the Philippines 
by one species each. Lygodium is represented by six species 
which are conspicuous climbing ferns very unlike their single dimin- 
utive representative in our Eastern States. 
FaMILy 4. GLEICHENIACEAE 
This family is well represented ‘in the Philippines by eleven 
species of Dicranopteris ; + while this number is nominal it is likely 
not to be excessive, judging from the diversity of species in other 
tropical regions. The species are wide-spreading, often forming 
tangled thickets, and are easily recognized by the pseudo-dichot- 
omous branching. They are very difficult to prepare for the her- 
barium and the greatest care should be taken to secure represen- 
tative material, since the apical portions of a branch may be quite 
unlike the lower part of the same plant. By all means the lowest 
forking should be included in the specimen. 
* In case the members of this alliance are grouped as a single genus it must bear 
the name Lophidium, the oldest available name for a member of this group. The three 
genera, however, are very homogeneous groups and may best be treated as above. 
+ The 3 Mertensia of Synopsis Filicum has been thought by many, commencing 
with Willdenow, to be worthy of generic rank, and has often been kept distinct from the 
typical Australasian species of Gleichenta. The name Mertensia, however, is not 
available since there is an earlier Mertemsia in the Borraginaceae. Dicranopteris 
Bernh. is available for this group and was proposed for what has usually been known as 
Gleichenia dichotoma (Polypodium dichotomum Thunb.). Mecosorus Hassk. was a 
later name proposed by its author because of the preoccupation of Meriensia. 
