28 Evans: HeEpaticAE OF PuERTO RIco 
or spinose-dentate, 0.25 mm. long, 0.1 mm. wide, lobule irregular 
in shape, 0.15 mm. long, 0.07 mm. wide, laciniate ; bracteole 
more or less connate on one side, ovate, 0.2 mm. long, 0.15 mm. 
wide, bifid about one half with attenuate divisions, margin irregu- 
larly spinose-dentate ; perianth oblong, five-keeled, keels slightly 
spinose at the apex, postical keels long and narrowly decurrent, 
parallel, beak tubular, long for the size of the plant: ¢ inflo- 
rescence on a short branch ; bracts in one or two pairs, imbricated, 
strongly inflated, the lobe orbicular, abruptly acute at the apex, 
lobule subacute, keel roughened in the outer part: antheridia 
borne singly (f/. 2, f. 14-23). 
On living leaves. El Yunque, Evans (36 p.p., 197). Origi- 
nally collected in Brazil by Ue. 
D. Araucariae is related more or less closely to the four fol- 
lowing species under which its differential characters will be noted. 
It may be stated here, however, that it differs from all of them in 
its smaller size and in its smaller leaf-cells. It is in fact the small- 
est and most delicate of all known Drepanolejeuncae from Puerto 
Rico. Its propagula offer little that is distinctive. The rudimen- 
tary leaves behind which they arise are sometimes borne on spe- 
cialized axes and are sometimes scattered among normal leaves. 
The description of the perianth is taken from Stephani. 
Drepanolejeunea dissitifolia sp. nov. 
Brownish-green, growing in thin irregular patches : stems 0.04 
mm. in diameter, prostrate, irregularly pinnate, the branches 
widely spreading: leaves distant, the lobe obliquely spreading in 
the lower part, widely spreading above, somewhat convex, falcate- 
lanceolate, 0.3 mm. long, 0.09 mm. wide, slightly narrowed at the 
base and attached by an almost longitudinal line of insertion, mar- 
gin entire or slightly crenulate or denticulate from projecting cells, 
apex acute to short-acuminate, ending in one cell or in two super- 
imposed cells ; lobules strongly inflated, ovate, 0.1 mm. long, 0.07 
mm. wide, keel strongly arched, roughened in outer part from 
projecting cells, free margin slightly curved, involute near base, 
passing beyond apex by a lunulate sinus to end of keel, apical 
tooth strongly curved ; leaf-cells plane or slightly convex, thin- 
walled, averaging, 16x12; ocelli none: underleaves distant, 
basal portion quadrate to trapezoidal, 0.045 mm. long, marginal 
cells usually six to eight, rarely as many as ten, divisions widely 
spreading, sometimes at an angle of 180°, having a spread of 0.15 
mm., each three or four cells long and two cells wide at base: 
