166 FERNS : BRITISH AND FOREIGN. 
forked ; costa excentric ; venules direct, free, their apices clavate, 
the anterior one sporangiferous. Receptacles oblong. Sori 
terminal, elliptical, marginal. Indusium oblong, attached lon- 
gitudinally, hippocrepiform. 
1. D. lunulata, Desv. ; Hook. Gard. Ferns, t. 17. Didy- 
mochlaena truncatula, J. Sin. Gat. Cult. Ferns (1857). 
Aspidium truncatulum, Sic. Aspidium squamatum, 
Willd, ; (Plum. Fil. t. 56). Didymochlaena 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. StnitJiiopterece. Fertile fronds contracted; segments 
revolute , forming a universal indusium, enclosing crowded 
pundiform sori. 
82. STRUTHIOPTERIS, Willd. 
Vernation fasciculate, erect. Fronds pinnate or bipinnate 
1-3 feet high. Veins pinnate ; venules free, the fertile pinnae 
contracted, linear, with membranous, revolute, conniving mar- 
gins, forming a universal indusium. Receptacles medial, base 
