xxxviii. GENERA OP FEENS: 



45. CHEILATiTTHES, Swartz, Synop. Fit, 5, 126. 



ChntNiA, Hamilton MS., (Don.) ; OTHONOLOMA, Link. ; PHYSAPTKWS, 



Presl ; MrBiopTEBis, Fee ; ALEUBiTOPTEBis, Fee ; ADIANTI sp., Auct. ; 



AILOSOBI sp., Auct.; PTEBIDIS sp., Auct.; CASSEBEEBJE sp., J. Smith; 



NOTHOCHL;ENJE sp., Auct.; HYPOLEPIDIS sp., Auct.; ACBOSTICHI sp., 



Auct. ; PELL^* sp., Auct. ; ADIANTOPSIDIS sp., Fee. 

 Sori indusiate, transverse marginal, generally on a reflexed 

 tooth or lobule ; normally sub-orbicular, small, distinct, some- 

 times contiguous, and by lateral confluence, elongate : the recep- 

 tacles punctiform at the apex of the veins. Indusium membra- 

 naceous, or formed of revolute portions of the slightly altered 

 margin, of the same form as the sorus. Veins simple or forked 

 from a central costa ; venules free. 



Fronds usually small, pinnate variously pinnatifid or bi-tri- 

 pinnate; membranaceous or sub-coriaceous, sometimes pulverulent 

 or densely hairy or scaly beneath. Stipes and rachis generally 

 ebeneous. Rhizome tufted or shortly creeping. There is usually 

 much confusion as to the species referred by different botanists 

 to the genera Cheilanthes, Pteris, and Allosorus, arising from 

 what we believe to be, an erroneous view of the latter, which ia 

 well represented by A, crispus, and is essentially polypodioid, with 

 revolute but not indusiate margins. There is no place for an in- 

 termediate genus the Allosorus of Presl and authors between 

 Cheilanthes and Pteris, for there are but two types of structure 

 referred to these three groups : the sorus is either seated on a 

 punctiform receptacle, which is Cheilanthes, or on a linear elon- 

 gated receptacle, which is Pteris. The continuity of the indu- 

 8ium is perfectly immaterial. Cheilanthes thus only becomes an 

 intelligible genus. The group Physapteris, Presl, (Myriopteris, 

 Fe'e), is distinct in appearance, but does not afford any good dis- 

 tinctive character of generic importance, either in the veins or sori. 



Eucheilanthes. Segments with distinct or sometimes confluent indu- 



sia; not pouch-shaped. 



Ex. : C. micropteris, S o. C. nitidula, Hk. 



C. hirta, Sw. 

 C. intramarginalis, Sk. 

 C. aurantiaca (Pteris, Cap.; C. ochra- 



cea, Hk J 



Physapteris. Segments small, roundish, pouch-shaped, the indusium 

 entire and almost closing over the back. 



C. arabica, Dene. 

 C. varians, Hook. 



Ex. : C. lendigera, Sw. \ C. ele 



: . endgera, Sw. \ C. elegans, Den. 



C. myriophylla, Dew. \ C. Feei (Myriopteris gracilis, Fee.) 



