CHARACTERS OF TRIBES AND GENERA. 149 



no other point of relationship with that genus, its whole 

 habit and structure resembling Goniopteris and Stegno- 

 gramma, while from Meniscium it is distinguished only by 

 the more zig-zag anastomosing of the venules. Although 

 it thus differs from these genera only in degree, I never- 

 theless think it desirable to adopt it as a genus. 



Sp. D. Griffithii, Moore, Bedd. F. Brit. Ind. pi. 150; 

 D. Wilfordi, J. Sm. (Hook. Fil. Exot., t. 93). 



These two species are very local, the first being a native 

 of Assam, the other of Formosa. 



Tribe 8. GRAMMITIDE^ (Plate 8). 



Fronds varying from simple to decompound multifid, and 

 from a few inches to several feet in height. Veins free or 

 anastomosing. Sori linear, free or united, discal ; sporangia 

 superficial or immersed in grooves, naked or included under 

 an universal indusium. 



OBS. According to the " Synopsis Filicum " this tribe, 

 as restricted by me, contains about one hundred species, 

 the greater number being represented by the genus Gymno- 

 yramma. In some genera of the section Cryptogramma the 

 sori are very short and even, nearly punctiform ; the 

 reasons for retaining such in this tribe are specially notified 

 under the genera of that section. 



GrammitidecB is represented in all Fern regions, especially 

 within or near the tropics. 



SERIES 1. Veins anastomosing in various ways. 



Sect. 1. HEMIONITIDEJJ. 



Venation uniform, reticulated, or the venules parallel and 

 angularly anastomosing, near to, or at the margin only. 

 Sori equally reticulate or connected on or next the margin. 



