12 POLYPODIACE.1^ OF THE PHILIPPINE ISLANDS. 



2. Fertile region not so restricted. 



3. Fronds articulate to rhizome. 



4. Fronds pinnate (32) Stenochlcena 



4. Fronds simple, dichotomous (62) Platycerium 



3. Fronds not articulate to rhizome. 



4. Fertile and sterile fronds alike. 



5. Fronds simple (59) Elaphoglossum 



5. Fronds pinnate (60) Achrostichum 



4. Fronds dimorphous. 



5. Veins free (7) Polybotrya 



5. Veins forming areolse along 



main veins (8) Stenosemia 



5. Veins anastomosing 

 copiously. 

 6. Sterile frond 2-pronged (61) Clieiropleuria 

 a. Fronds pinnate in plan (9) Gymnopteris 

 1. Sporangia gathered Into sori, which are sometimes 

 contiguous, or somewhat indefinite. 

 2. Sori elongate, not niarginal nor sunken. 

 3. Indusium wanting. 



4. Fertile veins oblique to costa. 



5. Veins free throughout (23) Coniogramme 



5. Veins free except near mar- 

 gin (26) Syngramme 



5. Veins anastomosing copiously. 



6. Sori anastomosing (24) Hemionitis 



6. Sori simple. 



7. Stipe not artic- 

 ulate (25) Loxogramme 



7. Stipe articulate 



to rhizome (54) Selliguea 



4. Fertile veins connecting main 



veins (5) Meniscium 



4. Sori parallel to costa, one on each 

 side. 



5. Frond pinnate (50) Tanitis 



5. Frond tripartite (51) Christopteris 



5. Frond simple and entire (52) Drymoglossum 



3. Indusium present Asplenie;e 



2. Sori elongate, sunken, fronds simple and 



entire (Vittarie.^s 



{Polypodium elongatum 

 2. Sori marginal or submarginal, protected by 



the Inflexed margin of the frond Pteride^ 



2. Sori marginal or submarginal, apical on their 



veins, Indusium opening toward margin Davallie^ 



2. Sori dorsal on the fronds, round or nearly so. 

 3. Stipe articulate to rhizome, indusium 



absent Polypodieje 



3. Stipe articulate to rhizome, indusium 



present Davallie.e 



3. Stipe not articulate to rhizome. 



4. Indusium fastened on all sides, 



rupturing in middle (1) Diacalpe 



4. Indusium, when present, not fast- 

 ened on all sides. 

 5. Veins all free, sori terminal. 

 6. Pinnae articulate to 



rachis (12) Ncphrolepis 



