Hepaticae of Puerto Rico 
Il, DREPANOLEJEUNEA 
By ALEXANDER W. EVANS 
(With Piartes 1-6) 
The close relationship which exists between Drepanolejeunea and 
Leptolejeunea has already been commented upon in the first paper 
of this series.* It may be added that the species of Drepanole- 
- seunea, like those of Leptolejeunea, are almost exclusively tropical, 
a single exception being found in D. hamatifolia (Hook.) Schiffn., 
a species originally known from western Europe but since reported 
from Puerto Rico and also from southern Africa.t Many species 
of Drepanolejeunea grow on living leaves, but others prefer rotten 
wood or the bark of trees, and D. hamiatifolia often occurs on 
rocks. Certain species creep through tufts of mosses or other 
hepatics from which it is often difficult to disentangle them. It 
is much more common in fact to find several closely related species 
growing together on a leaf or a piece of bark than to find a patch 
composed of a single species. 
In the ‘‘ Expositio Hepaticarum Portoricensium” of Hampe 
and Gottsche { three species of Lejeunea are included which are 
now referred to Drepanolejeunea. These are D. hamatifolia, to 
which attention has already been called, D. inchoata (Meissn.) 
Schiffn. and D. tenuis (R. Bl. & Nees) Schiffn. They were col- 
lected about fifty years ago by Carl Schwanecke in the vicinity of 
Humacao at the eastern end of the island. Only one of these 
species, 2. inchoata, has since been found in Puerto Rico and there 
is consequently some doubt regarding the determinations of the 
other two. JD. tenuis, for example, was first described from Java 
and although it has been reported from French Guiana § and also, 
much more recently, from Costa Rica,|| Spruce questions its oc- 
* Bull. Torrey Club, 29: 496. 1902. 
+ Pearson, Christiania Vidensk.-Selsk. Forh. 18863: 5. 
t Linnaea, 25: 337-358. 18652. 
4G. L. & N. Syn. Hep. 390. 1845. 
|| Stephani, Bull. Soc. Roy. Bot. de Belgique, 31: 179. 1892. 
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