322 
KEYS TO THE FERNS OF BORNEO 
c 1 - Indusia not uniform, some of them 
elongate on one side 
■a 1 . Veins not free. 
b. Frond simple, or pinnate in plan. 
45. A thy Hum {part). 
c. Veins uniting regularly in pairs 
34. Dryopteris {part). 
c l . Veins uniting irregularly 
b 1 - First division of frond dichotomous. 
40. Tectaria {part). 
c. Frond erect, fan-shaped 
51. Matonia. 
< T - Frond pendent, sympodial 
52. Phanerosorus. 
E. DAVALLIEiE (in part). 
Sori dorsal on frond, mostly terminal on veins, roundish, indusium fixed by base 
or by base and sides. 
a. Stipe not articulate to rhizome. 
b. Rhizome erect 
b l . Rhizome creeping. 
32. Acrophorus. 
c. Fronds less than 10 cm. long 
c*. Fronds larger. 
25. Protolindsaya. 
d. Frond glabrous 
4. Tapeinidium. 
d 1 . Frond more or less hairy 
■ al - Stipe articulate to rhizome. 
b. Indusia fixed by base and sides. 
c. Paleae on rhizome hair-like. 
3. Microlepia. 
d. F'ronds simple, coriaceous 
24. Scyphularia. 
d 1 ' Fronds compound, thinner, hairy 
19. Davallodes {part). 
cl - Paleae broader, scale-like 
bi Indusia fixed by base only. 
23. Davallia. 
c. Frond and indusium coriaceous 
21. Humata. 
ci. Frond and indusium thinner 
20. Leucostegia. 
F. CYATHEEAE and WOODSIE.E. 
Sorus dorsal, globose f, indusium fixed beneath or by 
top or irregularly. 
u. Annulus oblique, complete, mostly tree- 
the margin, opening at the 
ferns 
m. Annulus vertical, incomplete, caudex erect, 
30. Cyathea. 
not arborescent 
31. Diacalpe , 
G. ASPLENIEiE. 
Sori elongate along a non-marginal vein, provided with an indusium attached to 
the vein and opening along the other side. 
a. Sorus on a special vein parallel to costa 49. Blechnnm. 
a*. Sori on ordinary oblique veinlets. 
b. Veins uniting regularly in pairs; indu¬ 
sium glandular-hairy 35. Mesochlaena. 
f Dipiaziopsis, with oblong sori and membranaceous fronds, is likely 
to be found in Borneo: its number would be 45A.] 
