J. SMITH ON THE GENERA OF FERNS. 65 



ced on the crossings of the venules, forming an oblique linear 

 sorus, parallel with and between each two of the costaeform 

 veins. Fronds simple, linear-lanceolate, or rarely pinnatijid, 

 the fertile sometimes slightly contracted. Sori oblique, contin- 

 uous, rarely interrupted, sometimes broad. 



Exanip. 1. S. Hamiltoni; Presl. (Grammitis, Wall.) 2. S. 

 heterocarpa ; -B/«»»e. 3. S. flavescens; (Grammitis, Wall.) 4. 

 S. macrophylla; Blume. 5. S. pothifolia; (Hemionitis, 

 Ham. Don, Grammitis decurrens, Wall.) Jllust. Hook, et 

 Grev. Ic. Fil. t. 5, 6. Blume, fi. jav. t. b\, 52, 53. 



Obs. AfTreeins: in habit and venation with some of the 

 simple fronded species of the Dipteris section of Drynaria ; 

 but, in the present genus, the sporangia are produced in a 

 line between the costffiform veins, which character may 

 readily be conceived to be formed by a linear confluence of 

 the sporangiferous points of such species as Drynaria crassi- 

 folia, D. hemionitidea, and some others, and indeed it is diffi- 

 cult to deny some states of Drynaria hemionitidea a place in 

 Selligitea. 



28. DiBLEMMA, J. Sm. 



Venation uniform, reticulated; areoles unequal, producing 

 simple or brachiate, straight or curved, free, recurrent vein- 

 lets. Sporangia produced on the transverse marginal anas- 

 tomosing of the venules, forming a linear, continuous, margi- 

 nal sorus, and also on the recurrent veinlets forming round 

 or oblong or irregular sori. Fronds simple, linear-lanceolate, 

 and attenuated, 1 8 itiches in length, by about i an inch in width, 

 slightly repand, and membranaceous. Sori formed of but few 

 sporangia. 



Species. D. Samarensis; J. S?n. — Hook. Jour, of Bot.p. 399. 



Obs. This simple-looking fern has the venation of some 

 species of Drynaria vinA the foWo-win^geuwsDrymogloss^im, and 

 is ^peculiar in having the simple round sori of Drynaria and 

 the compound elongated marginal sorus of Drymoglossum on 

 the same fronds. This double character goes some lencfth to 

 prove that the transverse elongated sori of Tcenitis and its 



Vol. IV._No. 2(i. 1 



