168 CHARACTERS OF TRIBES AND GENERA. 



Illust. Hook, and Grev. Ic. Fil., t. 178 ; Hook, and 

 Bauer, Gen. Fil., t. 13; Moore Ind. Fil., p. 55, A.; 

 Hook. Syn. Fil., t. 6, fig. 49. 



OBS. This genus is founded on a very peculiar Fern, 

 which 011 account of the reflexed margin of the pinnae was 

 referred to the genus Pteris by Swartz, but it having been 

 found that the sporangium was produced in the centre of 

 the pinnae, in the form of a single round sorus, led to its 

 being characterised as a distinct genus by Hooker and 

 Greville, under the above name, in the " Genera Filicum," 

 however, Sir William Hooker says that " Mr. Bauer's 

 dissections, and Mr. Smith's investigations, show that there 

 are several small sori, which eventually become confluent." 



This is one of the peculiar Ferns spoken of at page 12 

 of the Introduction, that continue to form and develope 

 pinnae from the apex of the frond, which lengthens indefi- 

 nitely as long as the plant continues to receive influences 

 favourable to its growth. 



It is found only in the Andean regions of Tropical 

 America, where it has a wide range, presenting different 

 appearances in the various localities in which it is found : 

 the different states being described by Kunze under at least 

 five distinct species, which in the " Species Filicum " are 

 considered as only synonyms of J. imlricata. Mr. Spruce, 

 however, who has studied them in their native localities 

 informs me that he considers there are at least two distinct 

 species, and also refers Gymnogramma elongata to this genus. 



Sp. J. imbricata, Hook, and Grev. Ic. Fil., t. 178 (/. sea- 

 laris, Kunze Fil., t. 71 ; /. verticalis, Kunze Fil., t. 82 ; 

 /. canescens, Kunze, in Schk. supplt., t. 133 ; /. cinnamonea, 

 Kunze, in Schk. Fil. supplt. t. 71) ; J. elongata, Fee. 

 (Gymnogramma elongata, Hook., in Journ. of Sot., 1834, 

 p. 61, t. 119). 



