514 JUNGERMANNIACEAE. 



12. LEPTOLEJEUNEA [Spruce] (Schiffn. in E. & P. Nat. 

 Pflf. I 3 : 126. 1894. 



Plants prostrate, small, irregularly but often copiously branched, the 

 branches as in Eadula. Leaves complicate-bilobed, the dorsal lobe usually plane, 

 obtuse to acute; lobule as in Lejeunea, with a hyaline papilla at the proximal 

 base of the apical tooth; leaf-cells thin-walled but sometimes with distinct 

 trigones; ocelli usually present. Underleaves distant and minute, with widely 

 spreading, subulate divisions. Antheridia usually in pairs, in the axils of 

 saccate bracts, the androecia variable in length. Female inflorescence borne 

 on a very short branch, simple or with a single subfloral innovation. Perianth 

 sharply five-keeled in the upper part, the keels projecting upward as entire 

 horns. Vegetative reproduction by means of caducous branches with special- 

 ized basal leaves. [Greek, delicate \Lejeunea.~] A genus of about 50 tropical 

 species. Type species: L. elliptica (Lehm. & Lindenb.) Schiffn. 



1. Leptolejeunea elliptica (Lehm. & Lindenb.) Schiffn. in E. & P. Nat. Pflf. 

 I 3 : 126. 1804. 



Jungermannia elliptica Lehm. & Lindenb. Pug. 5: 13. 1832. 



Pale green, becoming blackish or brownish with age, growing in thin 

 patches. Leaves distant, the dorsal lobe widely spreading, oblong-ovate to 

 oblong-lanceolate, about 0.35 mm. long, rounded to subacute, entire; lobule in- 

 flated, ovate, the apex tipped with a single, almost straight cell ; leaf -cells with 

 small but distinct trigones, averaging about 23 /A; ocelli two to five, in an inter- 

 rupted median row; divisions of underleaves formed of two or three cells in a 

 single row; inflorescence autoecious or dioecious; female branch without an 

 innovation; bracts scarcely complicate, usually bilobed; bracteole connate on 

 both sides, linear, shortly bifid ; perianth obconical, terete below, the horns acute 

 or truncate. 



On bark, Soldier's Road, New Providence: Florida; widely distributed in the 

 tropical regions of America, Asia, and the Pacific Islands ; usually growing on living 

 leaves. ELLIPTIC LEPTOLEJEUNEA. 



13. BRACHIOLEJEUNEA [Spruce] Schiffn. in E. & P. Nat. 

 Pflf. I 3 : 128. 1894. 



Plants prostrate or pendulous, medium sized to large, irregularly branched, 

 some of the branches usually as in Frullania, the others as in Eadula, color 

 often dark brown or nearly black. Leaves imbricated, complicate-bilobed, the 

 dorsal lobe squarrose (at least when moist), ovate, rounded to apiculate or 

 acute, entire; lobule inflated along the keel, appressed to the dorsal lobe along 

 the crenulate or dentate margin, hyaline papilla at the proximal base of the 

 apical tooth, displaced from the margin; leaf-cells with distinct trigones. 

 Underleaves undivided, orbicular to reniform, entire. Antheridia in paroe- 

 cious species borne singly in the axils of scarcely modified bracts, in autoecious 

 species borne in pairs in the axils of saccate bracts, the androecia in the latter 

 case long and often proliferating; bracteoles everywhere present. Female in- 

 florescence borne on a more or less elongated branch, with one or commonly 

 two subfloral innovations; bracts scarcely complicate but often winged along 

 the keel, unequally bilobed; bracteole rounded to shortly bilobed. Perianth 



