218 Evans: HEPATICAE OF PUERTO RICO 
Diplasiolejeunea unidentata Schifin. Bot. Jahrb. 23: 583. 1897. 
Pale green or whitish, growing in compact depressed tufts: 
stems 0.14 mm. in diameter, prostrate, irregularly pinnate, the 
branches obliquely to widely spreading, similar to the stem but 
usually with smaller leaves: leaves imbricated, the lobe widely 
spreading, somewhat convex, broadly ovate to suborbicular, 
1.2-1.4 mm. long, I-1.2 mm. wide, antical margin straight to 
rounded at the base, usually arching across the axis, strongly out- 
wardly curved to the apex, postical margin also curved, forming 
a very obtuse or rounded indentation at the junction with the 
keel; lobule obovate, 0.7 mm. long, 0.4 mm wide, inflated along 
the arched keel, more or less appressed to the lobe in the outer 
portion, free margin involute near the base but usually plane 
otherwise, apical tooth acute, obliquely spreading, mostly three 
to five cells long and two or three cells wide at the base, usually 
tipped with two superimposed cells, proximal tooth much shorter 
and often inconspicuous, acute to rounded, hyaline papilla mostly 
distal, sinus shallow, forming a distinct angle with the apic 
tooth; cells of lobe averaging 18u at the margin, 28 X 18m 
the middle and 32 X 18 at the base, more or less thickened and 
usually with distinct trigones and_ occasional intermediate 
thickenings: underleaves distant to subimbricated, broadly 
cuneate, 0.2 mm. long in the middle, 0.5-0.6 mm. wide, bifid 
about one half with obliquely spreading divisions, obtuse to rounded 
at the apex, sinus mostly acute, margin entire: inflorescence 
dioicous: @ inflorescence borne on a leading branch or on a more 
or less abbreviated branch, the innovation mostly simple and 
sterile; bracts obliquely spreading, sharply complicate and some- 
times very narrowly winged along the keel, bifid one third to one 
half, the lobe oblong, 0.6 mm. long, 0.25 mm. wide, rounded 
apex, entire, lobule similar in form, 0.5 mm. long, 0.22 mm. 
rounded to very obtuse at the apex, margin entire; bracteole ovate, 
0.45 mm. long, 0.35 mm. wide, bifid about one third with acute 
suberect divisions and an entire margin; perianth as in D. pellucida 
I.3 mm. long, 0.75 mm. wide: o& inflorescence occupying a short 
branch, not proliferating; bracts mostly in from three ‘0 - 
pairs, similar to those of D. pellucida; bracteoles also similar: 
mature sporophyte not seen. (PLATE 17, FIGURES I-12.) 
On bark, rarely on leaves. El Yunque, Evans (2, 120 in par 
145). The species is known to the writer from the ol 
additional localities: Mansfield, Jamaica, Evans (336); Sharfo 
Estate, Dominica, Elliott (1601); Martinique, Duss; 5t- Vincen! 
Herb. Hooker, the type station. 
wide, 
