158 CHARACTERS OF TRIBES AND GENEKA. 



Illust. Hook, and Bauer, Gen. Fil., t. 37 ; Hook. Gard. 

 Ferns, t. 50; Moore Ind. Fil., p. 48; J. Sin. Ferns, 

 Brit, and For., fig. 50 ; Hook. Syn. Fil., t. 6, fig. 32, A. 



OBS. This genus as here restricted, includes a consider- 

 able number of species varying greatly in size and circum- 

 scription of the fronds, but all agreeing in having the 

 sporangia produced on forked free veins, forming linear, 

 naked sori, examples of the extreme sizes being represented 

 on the one hand by G. leptophylla, an annual a few inches 

 high, and the magnificent species, G. javanica and G. pro- 

 cera (Coniogramma, Fee\ which have fronds 2 to 5 feet 

 high, with broad pinnae. 



These differences have induced some authors to cha- 

 racterise the different groups as distinct genera, of which 

 Professor Link has five, and with some alterations M. Fee 

 makes ten, the whole including about forty species. Sir 

 William Hooker, in his " Species Filicum," goes much 

 beyond this ; he includes all Ferns with oblong, linear, 

 oblique, naked sori, thus including species with both free 

 and anastomosing venation, under which he describes 

 seventy-five species, thus making it a more unnatural 

 genus than when it was in its original state ; he, however, 

 divides them into six sections, the last including the genus 

 Selliguea of Bory, which belongs to the division Eremobrya, 

 and therefore has no natural relationship with Gymno- 

 gramma. With regard to true Gymnogramma, I consider it 

 best to adopt, so far as I find convenient, Link and Fee's 

 generic names as sectional names only. 



1. Fronds simple, entire, reniform, smooth (Pterozonium, Fee). 

 G. reniformis, Mart. Hook. Second Cent, of Ferns, t. 9. 



2. Fronds simple, entire, linear lanceolate, smooth (Asple- 



nitis, J. 8m.'). 

 G. marginata, Mett. 



