158 Evans : Hepaticae of Puerto Rico 



approximately obovoid in shape and rounded to truncate at the 

 apex, with a short beak. It is sometimes terete and sometimes more 

 or less compressed, but even in the latter case the lateral keels are 

 never sharp. The postical surface bears from two to five keels, and 

 the antical surface is either plane or provided with three or four keels 

 (figures 21, 22). All of the keels are rounded and are never 

 winged or toothed in any way. In pluriplicate perianths they are 

 separated from one another by deep grooves, and there is no dif- 

 ference, except in position, between the lateral keels and the others. 

 In autoicous and dioicous species the male spikes are long and 

 often proliferate at the apex. The bracts are imbricated and tend 

 to be smaller than ordinary leaves, but their lobules are relatively 

 larger and more strongly inflated. Even here the free margin of 

 the lobule is usually more or less toothed. The antheridia occur in 

 pairs, and the bracteoles are found throughout the entire length of 

 the spike. In paroicous species the bracts are much fewer and are 

 essentially like normal leaves; they differ also from the bracts just 

 described in bearing the antheridia singly. 



The present genus is in most respects clearly defined. The 

 squarrose leaves, the large lobules with teeth along the free mar- 

 gin, the subfloral innovations usually occurring in pairs, and the 

 phcate perianth with unarmed keels afford an excellent combina- 

 tion of generic characters. Certain species, however, as Spruce 

 has already pointed out, show a relationship with Marchesinia, 

 while others are even more closely allied to the genus Ptychocoleus 

 as restricted in the present paper. In most species of Marchesinia 

 the free margin of the lobule is also denticulate and the sub- 

 floral innovations occur in pairs, but the leaves are not squarrose 

 and their lobes are relatively smaller and very different in appear- 

 ance from those found in Brachiolejeunca. The perianth, more- 

 over, is distinctly compressed and plane on both antical and postical 

 surfaces. The characters which separate Brachiolejcunea from 

 Ptychocoleus will be considered under the latter genus. 



Two species of Brachiolejeunca, B. densifolia (Raddi) comb, 

 nov. and J^cort^/is (Lehm. & Lindenb.) Schiffn., have been re- 



f„rt lUt S P edeS ; S comm °nly known as B. bicolor (Nees) Schiffn., in spite of the 

 clT F : UUan ° ldeS ****** R *ddi and Jungermannia bicolor Nees have long been 

 consumed synonyms. Trevisan restored Raddi's specific name, but has not been fol- 



