( 3 ) 
Invol. double, opening outwardly* inner valve 
formed of slightly changed margin of 'frond. 
20 Lindsaya. 
. * 
Pinnse overrided, quadrant-shaped, 
t f f f Lin. orobl. 
Invol. formed of reflexed edge of frond, opening 
invjardly. 
Sori obi. globose to liiiear. 
(Segments onesided, text, pellucid), 21 AdIANTUM- 
Sori subglobose, becoming confluent and lin. 
25 Cheilanthes. 
Sori continuous linear ; connecting several veins. 
Invol. pressed down reaching from edge of seg- 
ment to midrib, 2 Onychitjm. 
Sori dotlike upon veins, soon becoming confluent 
and linear. 
(Habit of Cheilanthes ; text, coriaceous.) 
30 Pell^a 
Sori lin. continuous. 31 Pteris. 
Sori filling whole space between edge and midrib, 
frond dimorphous. 33 Lomaria. 
Frond floated by air-cells in water. 
32 Ceratopteris. 
Sori near midrib 
In parellel rows ; invol. subcoriaceous closing in 
sori. 36 Woodwardia. 
In continuous line ; invol. distinct from edge of 
fiond 33 Blechnum. 
Sori attached to veins, obliquely to midrib : invol, 
when single, opening towards midrib, (Asple- 
niese.) 
Invol. straight or curved (Athyr.) single, Euasple- 
nium and Darea, or double (Dipl. Anisog). 
38 Asplenium. 
a 
