134 ALEXANDER W. EVANS 



2. Lejeunea cladogyna sp. nov. 



Pale or dull green, sometimes becoming yellowish or brownish 

 with age, growing in loose mats: stems mostly 0.08-0.1 mrn. in 

 diameter, sparingly and irregularly pinnate, the branches widely 

 spreading and sometimes subdivided, often with smaller leaves than 

 the stem but not microphyllous : leaves contiguous to loosely imbri- 

 cated, the lobe obliquely to widely spreading, plane or slightly convex, 

 subfalcate, broadly ovate, when well developed about 0.45 mm. long 

 and 0.4 mm. wide, dorsal margin sometimes arching partially across 

 the axis, sometimes not, sometimes strongly outwardly curved from 

 the base to the broad and rounded apex, sometimes straight or slightly 

 incurved in the basal region, ventral margin slightly outwardly curved 

 to straight, margin entire throughout; lobule when well developed 

 inflated, broadly ovoid, 0.09-0.12 mm. long and 0.09 mm. wide, keel 

 straight or slightly arched, roughened from projecting cells, forming a 

 very broad angle with the ventral margin of lobe, free margin somewhat 

 involute to beyond the apex, sinus oblique and very shallow, apical 

 tooth a rounded, straight, slightly projecting cell with a hyaline papilla 

 or its proximal side; lobule usually poorly developed and reduced toa 

 minute basal fold; cells of lobe averaging about 16 ^ along the margin 

 and 28 X 18 /x in the median and basal portions, thin-walled through- 

 out or with minute and indistinct trigones and intermediate thicken- 

 ings, cuticle smooth ; ocelli none : underleaves distant, ovate to ovate- 

 orbicular, about 0.15 mm. long and 0.12-0. 15 mm. wide, bifid about 

 one half with an acute to lunulate sinus and erect, triangular, sub- 

 acute lobes, margin entire: inflorescence autoicous: 9 inflorescence 

 borne on a very short branch, with only one vegetative leaf and one 

 bracteole in addition to the involucral leaves, innovating on one side, 

 the innovation short and sterile (so far as observed) ; bracts obliquely 

 spreading, the lobe oblong to obovate, when well developed about 

 0.3 mm. long and 0.16 mm. wide, rounded at the apex, entire, lobule 

 about 0.2 mm. long and 0.08 mm. wide, narrowly oblong, the free 

 portion 0.06 mm. long or less, obtuse to rounded at the apex; bracteole 

 somewhat connate on one or both sides, oblong, about 0.3 mm. long 

 and 0.16 mm. wide, bifid about one fourth with a narrow sinus and 

 erect, rounded or very obtuse lobes, margin otherwise entire; perianth 

 long-exserted, narrowly obovoid, about 0.6 mm. long, and 0.3 mm. 

 wide, truncate at the apex and with a short beak, narrowed toward 

 the base, sharply five-keeled above the middle, the keels indistinctly 

 crenulate or denticulate from projecting cells, surface otherwise smooth : 

 cf inflorescence occupying a short branch, not proliferating; bracts in 

 two or three pairs, closely imbricated, strongly inflated, shortly bifid 

 with a strongly arched, crenulate keel, and blunt divisions; antheridia 

 in pairs; bracteole usually single at the base of the inflorescence, 

 minute, shortly bifid: mature capsule about 0.2 mm. in diameter. 

 [Fig. 2.] 



