CHAEACTEKS OF TRIBES AND GENKRA. 113 



toinosing. Receptacles panotiforiu or oblong linear, pro- 

 duced on fclie confluence of two or more excurrent arcuate 

 f einlets, terminating- in the medial areoles. Sori transverse 

 nniserial, furnished with indusiform peltate scales. 

 Type. Pohjpodimn percassmn, Cav. 



Illust. Hook and Bauer, Gen. Kl., t. 18 ; Moore Ind. 



Fil, p. 02, figs. 1, 2, 3, i; J. Sm., Ferns, Brit, and 



For., fig. 12. 



Oes. — In my genera of Ferns (1811) I made the genn.i 



Pleopeltis, as lounded hj Humboldt, a section of the genus 



Phlebodium of R. Brown, but now considering that habit 



assists to define groups of naturally allied species, and as 



the species of Pldehodiitm and those of the present group 



(Pleopeltis) differ entirely in habit, I deem it liest to retain 



the two as distinct genera. 



In order to show the diifurent views entertained b}' 

 Pteridologists respecting the limits of genera, I may here 

 mention that Mr. Moore, in his '" Index Filicnm," includes 

 under the genus Pleopeltis, the whole, or iu some cases 

 part only, of the species of no less than twenty-five genera, 

 of authors, of which he makes eight sections, which iu 

 most cases ditfer not only in habit, but also possessing other 

 special characters ; I am, therefore, induced to adopt them 

 as distinct genera. 



The following are the principal species tliat represent 

 Pleopeltis as hei'e restricted. The greater number a.re 

 natives of the West Indies and Tropical Aniei-ica, the threo 

 first are natives of the Ea-stei'u Hemisphere. 



* Fronds smooth, ijlabrous. [Lepisorus, J. Sm, 1846)- 



P. lineare (TJmnb.) ; (P. nnda, Hook. Ex. FL, t.63) (v v.) , 

 P. excavata (5or;/) ; (P. nuda. Honk- and Pnner, G'-n. Fd.^ 

 t.l8, iim Hook. Ey. Fl.> (v v.) 

 1 



