388 Evans: New West Indian Lejeuneae 



In 5. barbiflorum, which is especially close to the Haytian spe- 

 cies, the underleaves are constantly long-decurrent, and the brae- 

 teole is distinctly bifid. The two species agree in developing 

 many laciniae on the postical surface of the perianth, but these 

 laciniae are even more numerous in S. barbiflornm than in 5. lac- 

 eratiim and are also characterized by being shorter and more deli- 

 cate. In 5. vincentinnm the underleaves are usually broader than 

 long, agreeing in this respect with S. laceratnm, but they differ in 

 being constantly decurrent. Occasionally the leaves in this spe- 

 cies are apiculate as earlier authors have emphasized, but this con- 

 dition is far from constant and many plants bear rounded leaves 

 only. The bracteoleisretuse, irregularly sinuous-crenate, or emar- 

 ginate at the apex, and the perianth is either smooth on the posti- 

 • cal surface or bears only a few scattered laciniae. The laciniae 

 along the lateral keels tend to be shorter and less numerous than 

 in 5. laceratum. In Platylejennea Kroneana the underleaves are 

 also decurrent as in 5. vincentinum, but the bracteole is undivided 

 as in S. laceratum. The lateral laciniae of the perianth, however, 

 are reduced to spine-like teeth and the postical surface is smooth 

 or nearly so. In this species the lobules of the perigonial bracts 

 tend to be acute or apiculate instead of rounded, but this is a differ- 



. r 



ence which may well be inconstant. In the remaining species 01 

 Symbiezidium known from the West Indies the inflorescence is 

 dioicous. 



Yale University, 



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