Xl. GENSBA OP FEBKS: 



marginal twin firaotifications, which though not universally 



double, are commonly so. 



Ex. : C. pinnata, Xlfs, I C. gleichenioides, Gardn, 



C. triphylla, Klfi. \ C. petiolata, FSe. 



(d) Sori intramarginal, medial on the veins. 



48. PLECOSORTJS, Me, Gen. Ml. 150. 



Cbtptostigua, a. Sraun MS. ; Cheilakxkis sp.^ A. Brawn oZim, and 

 Auct. 



Sori (spuriously) indusiate, i.e., covered by the continuously 

 inflexed slightly attenuated or scariose margin of the segments ; 

 rotundate, intramarginal, seated among hair-like scales, becoming 

 eflfuse ; the receptacles prominent, medial. Veins forked from a 

 central costa, indistinct ; venules free. 



!Fronds large, pinnato-pinuatifid, densely scaly beneath. — The 

 ferns referred to this group differ from Cheilanthes in having 

 distinctly intramarginal medial, instead of marginal terminal sori. 

 They approach very near to Jamesonia, in company with which 

 they might perhaps be placed without violence to nature. We 

 retain them among the CheilantheiB, in consequence of the 

 transverse marginal — though scarcely more than spurious — 

 indusium, which is analogous to what occurs in some species of 

 Cheila/nthes. 



Ex. : P. pcruTianus, Fie. | P. speciosisBimus (Clieilanthes,^3r.> 



§ Pteelde*. 

 (a) Veins free. 



49. ONYCHITJM, KoMlfuss, Berl. Jahrl. FTia/rm. 45; Id. 



Enum. Ml. 144, t. 1. 



LiMOSTEOIl, Z).Dore; TElCHOMABia sp., Tinnier^ ; CsifOPTIBrDIS sp., 

 Thunberg ; DaB££ Bp., WiUdeTiow ; Phoeolobi sp., X>e»vattx; Cheil- 

 AHTHIS sp., Atict.; AltOSOEI sp., Pred ; PteeIBIS Bp., Auct. ; LOMAELiE 

 sp., Aucf. ; LOMAEIOBOTEYDIS sp., Fie ; ASPLENU 6p., Kllnze. 



Sori indusiate, Unear (or oblong) transverse margioal or sub- 

 marginal ; the receptacles continuous. Indusium linear (or 

 oblong), membranaceous, usually opposite, and whUe young 



