14 Evans: HeEpaTICAE OF PuERTO Rico 
sometimes microphyllous : leaves more or less imbricated, the lobe 
slightly to strongly convex, falcate-ovate, 0.6 mm. long, 0.35 mm. 
wide, attached by an almost longitudinal line of insertion, antical 
margin arching partially or wholly across the axis, almost straight 
near the base, then strongly outwardly curved to the rounded or 
very obtusely pointed apex, postical margin also outwardly curved, 
strongly indented at junction with keel; lobule ovoid, 0.17 mm. 
long, 0.1 mm. wide, narrowed in the outer part, strongly inflated 
throughout, keel strongly arched, slightly roughened from pro- 
jecting cells, free margin revolute but appressed to the lobe in the 
outer part, apical tooth sharp, commonly consisting of a row of 
two cells, appressed to the lobe, sinus nearly straight in an intact 
leaf, lunulate when flattened out; cells of lobe plane or slightly 
convex, averaging 8 # at the margin, 13 x 10 in the middle and 
23 X 144 at the base, walls more or less thickened with indistinct 
trigones ; ocelli and hyaline cells wanting: underleaves distant to 
contiguous, broadly orbicular, 0.2 mm. long, 0.25 mm. wide, some- 
times plane but usually reflexed along the sides and often at the 
apex as well, abruptly narrowed at the base and sometimes mi- 
nutely and indistinctly auriculate, apex broad, rounded or truncate: 
inflorescence dioicous: Q inflorescence on a more or less elongated 
branch, innovating on both sides, the innovations obliquely spread- 
ing, usually simple and sterile; bracts obliquely spreading, the 
lobe ovate, somewhat falcate, 0.75 mm. long, 0.45 mm. wide, 
antical margin much more curved than the postical, apex rounded, 
margin entire, lobule ovate, 0.2 mm, long, 0.15 mm. wide, rounded 
at the apex ; bracteole broadly orbicular-obovate, 0.5 mm. long, 
0.55 mm. wide, gradually narrowed toward the base, broad and 
rounded to truncate at the apex; perianth about half-exserted, 
1.25 mm. long, 0.75 mm. wide, obovate in general outline, gradually 
narrowed toward the base, broad and emarginate to obcordate at 
the apex with a distinct beak, antical face plane or with a broad 
median groove, lateral keels sharp, sometimes narrowly and indis- 
tinctly winged, dilated in the upper part into broad and rounded 
horns, postical keel sharply two-angled or rounded, occasionally 
bearing a low and short fold on its surface, often extended beyond 
short branch ; bracts mostly in 
bricated, strongly inflated, shortly and subequally bifid with rounded 
or bluntly pointed lobes and a strongly arched keel; bracteoles 
similar to the underleaves but smaller; antheridia and mature 
sporophyte not seen (PLATE I, FIGURES 17-23). 
On trees and rocks. Puerto Rico, without definite localities, 
Schwanecke, Sintenis (23). Also recorded from the following 
