314 
KEYS TO THE FERNS OF BORNEO 
Subgenus IV. PLEUROMANES. 
Costa bordered, and a marginal pseudo-vein 
present 18. T. pallidum. 
l8. T. PALLIDUM Bl. 
Probably common. 
Malaya to Ceylon, Polynesia and Queensland. 
Subgenus V. EUTRICHOMANES. 
a. Rhizome filiform, fronds usually under io 
cm. long. 
b. Fronds not over 3 cm. long, at most 
bipinnatifid. 
c. Margin toothed, frond smooth 19. T. serrulatum. 
c l . Margin entire, frond hairy 20. T. vestitum. 
b*. Frond 3—4 cm. long, sparingly tripin- 
natifid 21. T. Hosei. 
62. Well-developed fronds mostly 5—10 cm. 
long, freely tripinnatifid. 
c. Indusium ending in two small erect 
lips 22. T. micvochilum* 
ci. Mouth of indusium broadly dilated, 
scarcely two-lipped 23. T. pyxidiferum. 
ai. Rhizome woody, wide-creeping, fronds 
relatively large. 
b. Fronds pinnate or bipinnatifid, slender 24. T. auriculatum. 
bi. Fronds 4—5 pinnatifid, broad 25. T. maximum. 
a%. Fronds clustered, rhizome short- creeping 
or erect. 
b. Rachis winged throughout. 
c. Frond “ bipinnati-partite ” 26. T.ignobile. 
ci. Frond quadripinnatifid. 
d. Mouth of indusium toothed or ciliate 27. T. hispidulum. 
di. Mouth of indusium entire and naked 28. T. grande, 
bi. Rachis not winged throughout. 
c. Rachis and upper part of stipe naked. 
d. Bipinnatifid with forked “ pinnules ” 29. T. racemulosum. 
di. Well developed fronds quadripin¬ 
natifid 30. T. papillatum. 
ci. Stipe hairy throughout. 
d. Ultimate segments broad, short and 
obtuse * 31. T. saxatile. 
di. Ultimate segments tooth-like, linear 
or setiform. 
* Look out here for Hymenophyllum Foxivorthyi, with brownish lanceo¬ 
late fronds ( vide pp. 305—7 ante a ). 
