172 Evans : Hepaticae of Puerto Rico 



the genus which has been found in Puerto Rico is L. xanthocarpa, 

 although L. nnciloba (Lindenb.) Evans is surely to be expected 

 on the island. 



Leucolejeunea xanthocarpa (Lehm. & Lindenb.) Evans 



Jungermannia xanthocarpa Lehm. & Lindenb. in Lehmann, Pug. 



Plant. 5: 8. 1832. 

 Lejeunea xanthocarpa Lehm. & Lindenb. ; G. L. & N. Syn. Hep. 



330- 1845. 



887 s : 4. pi. i.f. 



'P 



Archilejeanea xanthocarpa Schiffn. Conspect. Hepat Archip. India 



316. . 1898. 



'pa Evans, Torreya 7 : 229. 1908. 



Pale glaucous-green, varying to bright-green and becoming 

 yellowish or brownish upon drying, growing in depressed mats :■ 

 stems 0.15 mm. in diameter, the branches obliquely to widely 

 spreading, with smaller leaves than the stem but not microphyl- 

 lous, sterile branches mostly simple or sparingly subdivided : leaves 

 imbricated and usually densely so, the lobe (when flattened out) 

 orbicular-ovate, 1 mm. long, 0.85 mm. wide, convex and strongly 

 revolute at the broad and rounded apex and along the whole pos- 

 tical margin, antical margin straight or slightly rounded at base, 

 then outwardly curved to the apex ; lobule narrowly ovoid, 0.4 

 mm. long, 0.2 mm. wide, gradually contracted in the outer half, 

 the water-sac opening directly into the revolute portion of the lobe, 

 keel straight or slightly arched continuous with revolute portion or 

 slightly indented at junction, apex (not visible without flattening 

 or dissection) varying from bluntly pointed to acuminate, in the 

 latter case tipped with a row of from two to four cells, sinus straight 

 or slightly lunulate, hyaline papilla mostly three to six cells from 

 the apex ; cells of lobe plane or slightly convex, averaging 14^ at 

 the margin, 20 fi in the middle, and 28 x 20 fi at the base : under- 

 leaves imbricated, plane (or a little convex from below), reniform, 

 0.5 mm. long, 0.7 mm. wide, rounded to cordate at the base, 

 rounded to vaguely retuse at the apex : $ inflorescence borne on 

 a more or less abbreviated branch, sometimes with only one pair 

 of leaves below the involucre, innovating on one side ; bracts 

 erect-spreading, the lobe falcate, convex, revolute at the rounded 

 apex and along the postical margin, oblong-obovate, 1 mm. long, 

 0.6 mm. wide, lobule oblong, 0.4 mm. long, 0.2 mm. wide, rounded 

 to subacute at the apex, keel sometimes narrowly winged ; brac- 

 teole broadly obovate, 0.95 mm. long, 0.75 mm. wide, slightly 



