ST ee ee 
Evans: HeEpATICAE OF PUERTO Rico 23 
each composed of a single row of cells. Unfortunately the lobule 
is often poorly developed and fails to show some of the pecu- 
liarities which have been described. 
The underleaves are broad and undivided, varying in outline 
from rotund to reniform (FIGURE 10). They are attached by a short 
and slightly arched line of insertion, and the margin, except some- 
times in the vicinity of the inflorescence, is entire. The underleaves 
are usually plane throughout but the median region sometimes 
bulges slightly toward the substratum, and in certain species the 
margin is revolute to a greater or less extent. The rhizoids are 
sometimes abundant and sometimes very few ; they grow out from 
the bases of the underleaves without the development of radicellif- 
erous discs. 
The inflorescence is usually autoicous but a few dioicous spe- 
cies have been described, and even in species which are normally 
autoicous unisexual individuals are not infrequent. The female 
branch is variable in length but is usually more or less elongated. 
In the majority of cases it is simple, occasionally it gives offa branch 
some distance behind the flower, and in very rare instances a true 
subfloral innovation is developed. The last condition, however, is 
doubtless abnormal and the absence of innovations may well be con- 
sidered a reliable generic character. The bracts differ considerably 
from ordinary leaves and are either dentate or spinose in nearly 
every species (FIGURES 17, 18). The lobule sometimes consists of 
a minute tooth at the base of the lobe and is sometimes much 
larger (PLATE 4, FIGURE 9), marked variations in these respects 
being occasionally exhibited by a single species. The bracteole is 
usually undivided as in ordinary underleaves, but its margin may be 
either toothed or entire. As in other genera without subfloral inno- 
vations there is a gradual transition from normal leaves and under- 
leaves to bracts and bracteoles, and for the sake of clearness it is 
perhaps advisable to restrict these latter terms to the floral leaves 
immediately surrounding the perianth. 
The perianth in Lopholejeunea presents some of the most strik- 
ing peculiarities of the genus (FIGURE 10). It is strongly com- 
Ht a a peared ee ag 
flowers but no perianths, Since no allusion is made to them in Schifiner’s ** Comspect. 
Hepat. Archip, Indici,”? published in 1898, it is possible that they were incorrectly 
determined. 
