J. SMITH ON THE GENERA OF FERNS. 163 



the substance of the frond. Sporangiferous receptacle distinct, 

 elevated. 



Examp. l.D. sagittlfolia; (Radd.). 2. D. hastata; {Radd.) 

 3. D. pa\mata. ; {Willd.) 4. D. coUina ; (Radd.). 5. D. 

 varians; (Radd.). 6. D. Wallichii, J. Sm. 7. D. cordi- 

 folia ; J. Sm. IHust Radd. Bras.fil. t. 63, 64, Qb. Hook. gen. 

 fil.t. 65. B./. 1. 



Ohs. The smooth, ebeneous stipes, and coriaceous texture 

 of this genus is similar to Platylotna, and some species of 

 Casseheera, but its reticulated veins readily distinguish it 

 from these two genera. From the followinfi it is not so 

 obviously distinct either in venation or in the sori, but the 

 habit of the several species are quite distinct from Litobrockia, 

 and clearly indicate a separate and natural group. 



58. LiTOBRocHiA, Presl^ J. Sm. 

 (Pteridis sp. Linn, and Auth, Campteria, Presl.) 



Venation external, elevated, arcuately or angularly reticu- 

 lated ; Creoles unequal, Sporangiferous receptacle transverse 

 marginal, constituting a linear continuous or interrupted 

 sorus. Indusiuin narrow, linear. 



Fronds from I to 8 feet high, pinnate or bi-tripinnate, ulti- 

 mate pinnce usually pinnati^d. Veins evident, sometimes only 

 the venules next the midrib or margin anastomosing. 



Examp. 1. L. splendens; (Kaulf.). 2, L. grandifolia; 

 {Linn.). 3. L. ampla; (Kunze.). 4. L. Haenkeana; Presl. 

 5. L. denticulata; (Siv.) 6. L. macilenta; {A. Rich.) 7. 

 L. spinulosa; {Radd.) 8. L. aculeata; {Sw.) 9. L. poiita; 

 (Link.). 10. L. decurrens ; Presl. II. L. macroptera; 

 (Link.). 12. L. podophylla; {Sw.). 13. L. vespertilionis; 

 [Labill.]. must. Hook, et Grev. Ic. Fil. t. 28. Schk. Crypt, 

 t. 92. Hook. Gen. Fil. t. 65. B./ 6. 



Obs. This is an extensive genus, usually characterized 

 with large branching compound fronds of a flaccid texture, 

 with superficial anastomosing or reticulated veins which dis- 

 tinguish it from Doryopteris, and true Pteris. 



The genus Campteria of Presl is founded upon three spe- 



