KEYS TO THE FERNS OF BORNEO 39 I 
b. Veins not more than once forked. 
c. Sori round 9. 
ri. Sori oblong. 
d. Branches of vein subequal 10. 
tP. Fertile branch very short. 
e. Hairs on stipe wine-colored. 
/. Hairs on frond 2—3 mm. long 11. 
/1. Hairs not over 1.5 mm. long 12. 
f?i. Hairs on stipe pale * 13. 
in. Veins with more than one branch. 
c. Hairs on stipe sparse, rather short 16. 
a. Hairs on stipe decidedly long. 
d. Sori in a single row on each side. 
e. Subcoriaceous, with inconspicuous 
veins 14. 
fi. Coriaceous, with conspicuous veins 15. 
£2. Sori pluriseriate or scattered. 
/. Sori in 1 or 2 irregular rows 17. 
/i. Sori in 3 or 4 rows or scattered. 
g. Almost glabrous 18. 
g 1 . Densely hairy 19. 
d 1 . Hairs on stipe dense, very short 20. 
P. sparsipilum. 
P. hirtellum. 
P. Broohsii. 
P. Reinwardtii. 
P. Havilandii. 
P. ccngenerum „ 
P. setosuin. 
P. pubinerve. 
P. diplosorum. 
P. calcipunctatum. 
P. multisorum. 
P. sumatranum. 
Section 2. Fronds delicate, linear, pinnatelv 
lobed to pinnate, with one sorus on each 
segment. “Monosoria.” 
a. Sorus more or less protected by folding of 
lamina “ Calymmodon.” 
b. Fertile segments narrowly stalked 
D. Fertile segments broad at base. 
c. Fronds under 5 cm. long 
c 1. Well developed fronds larger. 
d. Sterile segments obtuse, nearly hori¬ 
zontal 
di. Sterile segments at an acute angle. 
e. Sterile segments tooth-like 
£i. Sterile segments oblong, obtuse 
fli. Fertile segments flat. 
b. Frond lobed about half-way to costa, 
stipitate 
61. Frond cut two-thirds to costa, subsessile, 
segments close 
62. Frond cut very nearly to costa, segments 
remote 
22. P. clavifer. 
23. P. muscoides. 
21. P. strepiophyllum. 
25. P. cucullatum . 
24. P. gvacillimum. 
26. P. subpinnatifidum , 
27. P. murudense. 
28 9 P. alternidens. 
H 
