166 FERNS : BEITISH AND FOREIGN. 



forked ; costa excentric ; venules direct, free, their apices clavate, 

 the anterior one sporangiferous. Receptacles oblong. Sori 



Genus 81. Portion of mature frond, under side. No. 1. 



terminal, elliptical, marginal. Indusium oblong, attached lon- 

 gitudinally, hippocrepiform. 



1. D. lunulata, Desv. ; Hook. Gard. Ferns, t. 17. Didy- 

 mochlsBna truncatula, /. 8m. Cat. Cult. Ferns (1857). 

 Aspidium truncatulum, Sw. Aspidium squamatum, 

 Willd. ; (Plum. Fil. t. 56). Didymochlsena sinuosa, 

 Desv. ; Hook. Gen. Fil. t. 8. Diplazium pulcherrimum, 

 Radd. Fil. Bras. t. 59. Malayan Archipelago and 

 Tropical America. 



ff Sori destitute of special indusium. 



6. StrutUopterecB. Fertile fronds contracted; segments 

 revolute, forming a universal indusium, enclosing crowded 

 punctiform sori. 



82. STRUTHIOPTEBIS, Willd. 



Vernation fasciculate, erect. Fronds pinnate or bipinnate 

 1-3 feet high. Veins pinnate ; venules free, the fertile pinnee 

 contracted, linear, with membranous, revolute, conniving mar- 

 gins, forming a universal indusium. Receptacles medial, base 



