Evans: HEpATICAE OF PuERTO RIco 19 
wrapped around the stem, almost concealing the underleaves, 
antical margin of lobe arching across or a little beyond the axis, 
strongly outwardly curved from the base to the rounded apex, 
postical margin also rounded, forming an angle of 90° or more 
with the keel, margin entire or minutely and indistinctly crenulate 
from projecting cells ; lobule ovate in outline, 0.4 mm. long, 0.2 
mm. wide, inflated throughout, sometimes constricted in the outer 
part, keel straight or nearly so, slightly decurrent, forming an 
angle of about 45° with the axis (and base of lobule), free margin 
revolute to apex, sinus straight or nearly so, forming an angle of 
about 90° with the free margin, apex rounded or very obtuse, in- 
definite in structure, hyaline papilla marginal, borne at about the 
middle of the sinus; cells of lobe more or less convex, averaging 
13 #4 in diameter at the margin, 18 » in the. middle and 29 p» at the 
base, trigones very large, triangular in outline with somewhat 
bulging sides, separated by small pits or occasionally confluent, 
intermediate thickenings infrequent and usually minute, cell- 
Cavities substellate ; ocelli none : underleaves contiguous to slightly 
imbricated, broadly orbicular, 0.75 mm. long, 0.9 mm. wide, plane 
or more or less convex from below, abruptly narrowed and very 
short-decurrent at the base, attached by a strongly arched line of 
insertion extending about one third the length of the underleaf, 
apex broad and rounded, margin as in the leaves: inflorescence 
dioicous: Q inflorescence borne on a more or less elongated. 
branch, innovating on one side, rarely on both, the innovations 
simple or again floriferous ; bracts obliquely spreading, complicate, 
unequally bifid, the lobe obovate, 0.75 mm. long, 0.4 mm. wide, 
rounded at the apex, margin entire or irregularly sinuate, lobule 
ligulate, the free portion sometimes very short, 0.3 mm. long, 0.05 
mm. wide, rounded to obtuse at the apex, keel sharp, not winged ; 
bracteole free, oblong to obovate, 0.6 mm. long, 0.4 mm. wide, 
rounded to emarginate at the broad apex, margin as in the bracts ; 
perianth slightly exserted, obovoid or obconical, 0.85 mm. long, 
0.55 mm. wide, gradually narrowed toward the base, rounded to 
truncate at the apex and abruptly narrowed to a small circular 
Opening, beakless, terete or very obscurely triangular in cross- 
section, surface smooth : 3 inflorescence occupying a short pri- 
mary branch ; bracts in two to ten pairs, imbricated, inflated at the 
base, deeply and subequally bifid with ovate-triangular obtuse 
Obes : capsule 0.5 mm. in diameter; spores irregular in form but 
mostly longer than broad, about 25 y in short diameter, greenish- 
-rown, surface bearing scattered circular patches of minute and 
indefinite radiating ridges, otherwise minutely verruculose ; elaters 
measuring about 160 x 13 #4 (PLATE 3, FIGURES I-9). 
On trees, banks and rocks. Puerto Rico, without definite lo- 
