Britton: West Indian mosses 675 



Distribution: Jamaica, Cuba, Haiti, Porto Rico, Guade- 

 loupe, and Barbados to South America; also Mexico (Yucatan). 

 Illustration: Hedw. Descr. pi. u (from Swart?.' type). 

 Exsiccatae: Still. Musci Cub. Wright. q8. 



43. Turckheimia linearis (Sw.) E. G. Britton, comb. nov. 



Tortida linearis Sw. Fl. Ind. Occ. 3: 1765. 1806. 



Barbnla linearis Brid. Mant. Muse. 88. 1819. 



Trichostomnm lineare Broth. E. & P. Nat. Pfl. i 3 : 394. 1902. 



Habitat and type locality: "On dry calcareous rocks, His- 

 paniola." 



Distribution: Jamaica, Cuba, and Haiti. 



Our specimens from Jamaica and Cuba have a well-developed, 

 slender peristome, which disappears from the old capsules. I 

 believe this species to be congeneric with Turckheimia guate- 

 malensis Broth., which also shows traces of a peristome though 

 the capsules are all old. The section of the leaf in T. linearis is 

 remarkable for having two rows of guide-cells of about 10 cells 

 each in the costa, with a stereid band both above and below. The 

 costa is rather broader than in T. guitemalensis and smooth on the 

 dorsal side, showing as a prominent white rib to the leaf. It is papil- 

 lose on the upper surface and the cells of the blade bear several 

 minute papillae on both surfaces. This peculiarity of the costa 

 removes Turckheimia linearis from Trichostomnm; and although 

 there is but a single row of guide-cells in T. gitatemalensis, their 

 macroscopic resemblance is so close that they appear to be 

 congeneric. 



44. Isopterygium tenerum (Sw.) Mitt. Jour. Linn. Soc. 12: 499. 



1869 



Hypnum tenerum Sw. Fl. Ind. Occ. 3: 1817. 1806. 



Habitat and type locality: "On trunks of trees, mountains 

 of Jamaica." 



Distribution: Jamaica, Cuba, Haiti, Guadeloupe, Martinique, 

 St. Lucia, to Trinidad and South America; also Bermuda, and 

 Louisiana to Florida. 



Exsiccatae: Sull. Musci Cub. Wright. 107. 



