466 CXLIII. FILICES. 
nate sori, is not represented in South Africa, nor are any of the groups with 
anastomosing venation. Some of the species vary remarkably in the 
cutting of the frond. 
TrizeE 8. ASPIDIER. 
Sori globose or oblong, placed on the back of the segments 
with an involucre of the same shape covering them, of which 
the edges are free nearly or quite all round. 
20. DIDYMOCHLAENA, Desv. 
Sori elliptical, terminal on the veinlets; the involucre 
emarginate at the base, attached to the linear receptacle, free 
all round the edge.—Pappe and Rawson, p.15; Hook. and 
Baker, Syn. Fil. p. 248. 
A single cosmopolitan tropical species, which extends into Natal. 
21. ASPIDIUM, Swartz (in part), R. Br. 
Sori subglobose. Involucre orbicular, fixed by the centre. 
— Hook. and Baker, Syn. Fil. p. 248. Polystichum and Cyr- 
tomium, Pappe and Rawson, pp. 14, 15. 
5 Cape species, 4 belonging to sect. Polystichum, with ample 2- or 3- 
pinnate, coriaceous fronds and free venation; and 1 to sect. Cyrtomium, 
with simply pinnate fronds and veins uniting slightly towards the edge. 
22. NEPHRODIUM, Rich. 
Sori subglobose ; the involucre cordate-reniform, attached 
by the sinus.— Hook. and Baker, Syn. Fil. p. 259. Lastrea 
and Nephrodium, Pappe and Rawson, pp. 12 and 14. 
Texture of the frond herbaceous ; the pinne pinnatifid or still more di- 
vided, not jointed at the base.—5 Cape species, belonging to sect. Lastrea, 
which has the veins free; and 2 to Hunephrodium, in which the lower 
veinlets of the contiguous regularly-pinnated groups join at their points. 
23. NEPHROLEPIS, Schott. 
Sori globose, on the apex of an upper branch of a vein, 
generally near the edge of the frond. Involucre reniform or 
suborbicular. Pinne simple, articulated at the base, marked 
on the upper surface with white, chalk-like dots— Hook. and 
Baker, Syn. Fil. p. 800. 
A single common cosmopolitan tropical species reaches Natal. 
24, OLEANDRA, Cavan. 
Sori globose, inserted in a row near the base or below the 
centre of the compact, free veinlets. Fronds quite simple, 
the rhizomes wide-trailing and stems jointed—Pappe and 
Rawson, p. 18; Hook. and Baker, Syn. Fil. p. 302. 
1 tropical African species reaches Natal. 
