552 Evans: HeEpaTiCAE OF PUERTO RICO 
bifid ; the lobes are broader than in the leaves and tend to be more 
pointed, the lobules are rounded to retuse at the apex, and the 
keels are destitute of wings. The bracteole is free and larger than 
the underleaves but otherwise similar to them. 
The perianth is more or less concealed by the bracts and is 
oblong in outline varying to pyriform or obovate. It is strongly 
trigonous with sharp lateral keels and a high and narrow postical 
keel. In certain species supplementary keels, both antical and 
postical, are developed, but the trigonous character of the perianth 
still remains apparent. The principal keels are sometimes pro- 
vided with narrow and interrupted wings, which are destitute of 
teeth. The beak of the perianth is short but distinct. 
The male inflorescence is terminal on a leading branch but 
often proliferates at the apex. The bracts are numerous and 
crowded, bearing the antheridia singly, and the bracteoles extend 
along the whole length of the spike. 
The genera Mastigolejeunea and Thysananthus are so closely 
allied that the propriety of trying to keep them separate is perhaps 
questionable. In Mastigolejeunea the lobes of the leaves, the 
underleaves, the bracts, bracteoles and keels of the perianth are 
entire ; in Zhysananthus they are more or less dentate. In other 
respects the two genera are essentially alike. The subgenera 
Dendro-Lejeunea Spruce * and Phragmo-L ejeunea Schiftn., + sepa- 
rated from 7hysananthus on account of their lack of flagelliform 
branches, are now included by Schiffner { under Thysananthus 
and have never been recognized as genera. 
M. auriculata has recently been described by the writer, with 
figures and a full synonymy, in another connection. § In the 
-scbpcions paper, therefore, attention is simply called to its general 
distribution and to its local distribution in Puerto Rico. 
MASTIGOLEJEUNEA AuRICcULATA (Wils. & Hook.) Schiffn. 
On trees, rotten logs and rocks. Near Mayaguez, Heller 
(4462, 4463), Mrs. Britton & Miss Marble (649 p. p-)- Road 
from Arecibo to Utuado, Howe (378). The species is widely dis- 
lo, 7 s is widely OF 
Hep. Amaz. et And. 110, 1884. 
t Lebermoose der Forschungsreise S. M. S. Gazelle 24. 1890. 
¢ Engler & Prantl, Nat. Pflanzenfam. r*: £29, 3895. 
4 Mem. Torrey Club’ : 129. pl. 17. f. 10-19. 1902. 
