742 PROCEEDINCIS OF THE NATIONAL MUSEUM. vol. xxvii. 



the sori home iiiidwa}' to the nmrf^iii.s (4—6 pair.s to each pinna) on the 

 ohseure free simple veins, the sporangia mixed with a few hright- 

 brown hairs, similar hairs borne rather abundantly on both sides of 

 the lachis but sparing-l}^ along- the midveins and sterile veins on the 

 under surface; the sori at length nearly or quite confluent, covering- the 

 surface of the pinna from base nearly to apex and against the revolute 

 margins. 



Type in the United States National Herbarium, no. 427566; col- 

 lected from tr(^es on the heavily wooded upper slopes of John Crow 

 Peak, Jamaica, altitude 1,650-1,800 meters, by William E. ^Slaxon, ;^o. 

 13Ji,6^ April 1(S, 1003. The type sheet comprises two plants and several 

 detached fronds, all of which are perfectly characteristic of the species 

 as represented b}' the following specimens, all from Jamaica: 



Highest slopes of John Crow Peak, altitude 1,650-1,800 meters, 

 Underwood nos. 806, ^IfSG^^IfSGa; Maxon no, I'BdIf,. 



Base of John Crow Peak, altitude 1,500-1,650 meters, Undej'vjood 

 no. '2387 ; Maxon no. 1260. 



New Haven Gap, altitude 1,650 meters, Underwood nos. 973^ 1083, 

 1084; Ol'ute 7io. 111. 



Morces Gap, altitude 1,500 meters. Underwood nos. 509, 6Jf3; ^V. 

 Harris no. 7127. 



Blue Mountain Peak, W. Harris, no. 7kS7. 



Cinchona, altitude 1,500 meters, Underioood no. 2626. 



Specimens of this plant were referred by Jenman ^' to Poly podium 

 rigescens Bory^ described from the island of Bourbon. From that 

 species, however, P. rigens differs markedly in several characters 

 upon which Willdenow laid stress in his original description of the 

 latter species, and which were further brought out by Hooker and 

 Greville upon the occasion of their figuring an authentic specimen/ 

 It is distinguished by the hispid-pilose covering of its vascular parts 

 (7*. rigescens is described and figured as glabrous throughout), by its 

 greater size and relatively greater breadth, and by the oblong rather 

 than ovate-oblong shape of the pinna?. In these differences the Jamai- 

 can plants are perfectly constant. 



The species is apparently not rare in Jamaica. Jenman's remarks 

 upon its habitat and distribution are of interest: "Frequent on the 

 branches of trees above 5,000 feet altitude; among the most rigid of 

 all this miscellaneous group of species; uniformly found growing on 

 the branches of trees of the high ridges to which the distribution is 

 confined, not on the trunks as most of the other similar species do." 



«Bull. Bot. Dept. Jamaica 4:117. 1897. 



^ Polyjwdium rigescens ^ory; "Willdenow, Sp. PL 5:1<S3. 1810. 



<^ Hooker and Greville, Icon. Fil. 2: pi. liW. ISIJl. 



