18 Evans : Hepaticae of Puerto Rico 



Pale- or bright-green, becoming brownish with age, occasion- 

 ally forming small depressed mats but usually growing mixed with 

 other hepatics : stems 0.17 mm. in diameter, sparingly branched, 

 some of the branches with smaller leaves than the stem but not 

 microphyllous ; rhizoids few : leaves imbricated, the lobe falcate- 

 ovate when explanate, 1 mm. long, 0.85 mm. wide, antical mar- 

 gin strongly curved except at the very base, arching across the 

 axis, postical margin straight or slightly incurved, apex rounded 

 to obtuse, margin entire or indistinctly angular-sinuate; lobule 

 0.35 mm. long, 0.2 mm. wide, abruptly contracted in the outer 

 part, keel forming an angle of about go° with the postical mar- 

 gin of the lobe; cells of lobe averaging i8ju at the margin, 32 x 

 21 [i in the middle and 37 X 21 ft at the base, convex on both sur- 

 faces, outer wall strongly thickened especially in the middle of the 

 cell, trigones large, triangular with bulging sides, intermediate 

 thickenings rare, found mostly in basal region of lobe : under- 

 leaves distant, broadly orbicular, 0.4 mm. long, 0.5 mm. wide, 

 bifid about one third with broad, erect, acute to apiculate divisions 

 separated by an acute sinus; margin as in the leaves: inflorescence 

 dioicous : 9 branch usually with a single rudimentary leaf and a 

 single underleaf in addition to the bracts and bracteole; bracts 

 spreading, the lobe convex, falcate-obovate, 0.85 mm. long, 0.5 

 mm. wide, rounded at the apex, margin as in the leaves, lobule 

 oblong or lanceolate, 0.4 mm. long, 0.08 mm. wide, free portion 

 short, rounded to acute at the apex; bracteole free, oblong, 0.8 

 mm. long, 0.4 mm. wide, narrowed toward the base, rounded at 

 the apex and very shortly bidentate or retuse; perianth more than 

 half exserted, obovate in outline, 1.4 mm. long, 0.9 mm. wide, 

 narrowed toward the base, truncate or slightly retuse at the apex 

 with rounded outer angles, surface smooth or nearly so : <$ inflor- 

 escence with bracts in from two to four pairs ; bracts imbricated, 

 strongly inflated, shortly bifid with a strongly arched keel, both 

 lobes rounded at the apex; bracteoles one or two at the base of 

 the spike, shortly and variously bifid ; antheridia single or in pairs : 

 mature sporophyte not seen (plate 3). 



On trees. Puerto Rico, without definite localities, Schwanecke y 

 Sintenis. El Yunque, Evans (j8 p. p., 4.6 p. />., 62, pp.) Also 

 known from several of the Lesser Antilles, namely: St. Kitts, 

 Brentel, Britton & Cowell ; Guadeloupe, L Herminier ; St. Vincent 

 and Dominica, Elliott. Apparently through an error, the type 

 locality of the species was given as " Bourbon," and it has also 

 been recorded from Java. In all probability, however, its range 

 is restricted to the West Indies. 



