Evans: HEPATICAE OF PUERTO RICO 277 
The rudimentary leaves in A. crenata seem to be confined to 
the bases of vegetative branches and are not found in a similar 
position on innovations. They are often only four or five cells 
long by three or four cells wide and show practically no lobules. 
Usually only one or two leaves at the base of a branch will show 
this rudimentary structure. The species rivals A. exigua in 
fragility and agrees with it in possessing a paroicous inflorescence, 
the only difference being that in A. crenata one of the antheridia 
is commonly borne in the axil of a perichaetial bract. When 
compared further with A. exigua the lobes of the leaves are found 
to be plane or nearly so, to have their margins practically parallel, 
and to project for about half their length beyond the lobules. 
A. crenata differs also in the structure of the perianth, which is 
not only narrower than in A. exigua but is smoother in the upper 
part, the roughness being often confined to the indistinct keels. 
The fact that only one subfloral innovation is produced should 
also be emphasized. Unfortunately the species was collected in 
very small quantity. 
Aphanolejeunea s caefol'a (Gottsche) 
Lejeunea sicaefolia Gottsche, Abh. Bremen Naturw. Ver. 7: 362. 
1882 (nomen nudum). 
Lejeunea (Cololejeunea) sicaefolia Gottsche in Stephani, Hedwigia 
27: 290. pl. 12. f. 21-24. 1888. 
Pale green, scattered among other hepatics or growing in loose 
depressed mats: stems not zigzag, 0.025 mm. in diameter, spar- 
ingly and irregularly pinnate, the branches widely spreading, 
similar to the stem: leaves distant, obliquely to widely spreading, 
the lobe lanceolate, slightly falcate, 0.4 mm. long, 0.1 mm. wide, 
somewhat concave and often variously curved and contorted in 
outer part, apex acuminate, usually tipped with a row of two or 
three cells, antical margin spreading from the base, slightly curved, 
postical margin beyond the keel straight or nearly so, margin 
(except at the very base) denticulate or crenulate from projecting 
cells; lobule ovate, 0.17 mm. long, 0.1 mm. wide, similar to that of 
A. exigua; cells of lobe averaging 14u at the margin and 30 X I4u 
in median and basal regions, conical, thin-walled throughout or 
with a slight thickening at the apex of the cone: inflorescence 
autoicous: 9 inflorescence borne on a more or less abbreviated 
branch, innovating on one side, more rarely on both, the innova- 
