﻿Britton: Mosses of Danish West Indies 5 



sessile on a small brown vaginule, globose, 0.5 mm. in diameter, 

 sharply apiculate, indehiscent ; walls with irregular hexagonal 

 cells, 27-32 IX in diameter; spores brown, slightly roughened, 27- 

 30 ju in diameter, maturing in spring. [Plate i, fig. 7-13.] 



Type locality: — St. Thomas: Cowell Point, E. G. Britton gg, 

 February 2, 1913. 



Distribution: — St. Thomas: Water Island, 150, 156. 



This species belongs to the section Microbryum and is close to 

 P. Floerkeaniim, but differs in the less acuminate and less subulate 

 leaves with plane margins without a yellow border, and more 

 chlorophyllose and papillose cells. 



13. Tortula agraria (Sw.) Sw. F1. Ind. Occ. 3: 1763. 1806 

 St. Jan: Bethania, Breutel; Bethania, Britton & Shafer 241, 

 268. St. Thomas: on limestone walls of old cemeteries, Breutel; 

 on damp earth, Nisky, 77; Cowell Point, p7; old walls, Crown 

 Estate, 450 m. alt., ijdp; on rocks atwaterfall, Magen's Bay, 131S; 

 stone walls. Bonne Resolution School, 442. 



; E. G. Britton sp. nov. 



Plants gregarious, in loose soil, brown at base and also more 

 or less brown above, from the excurrent awns; stems dull green, 

 slender, erect and mostly simple, unbranched, not more than 

 5 mm. high, matted with brown tomentum at base; leaves 

 erect-appressed when dry, not twisted nor glossy; spreading when 

 moist, less than i mm. long by 0.2 mm. wide; costa wide at base 

 40 /i (at least .2 width of leaf), excurrent into a short subulate 

 brown awn, slightly toothed at apex and on awn; cells of blade 

 hexagonal, 27-40 n long X 10 /x wide, basal cells shorter, oblong, 

 with a long, decurrent narrow wing of one row of cells, extending 

 down the stem to the next leaf; margins bordered by one row of 

 longer narrow cells 5 m X 54 M long, slightly revolute below and 

 serrulate above; only known from sterile specimens. 



Type locality: — Anagada: rocky plain near settlement, 

 Britton & Shafer 1038. 



Distribution: — Mona Island, Britton & Hess 1751, 1753. 



These specimens have been compared with type specimens of 

 B. decursivum C. Mull, from Porto Rico, kindly loaned to us by 

 Dr. Engler from the Royal Botanical Garden at Berlin, and, 

 though closely related by the decurrent narrow basal wing, ours 

 differs in its shorter leaves, serrate margins and shorter cells. 



