JUNGERMANNIACEAE. 511 



complicate-bilobed, the dorsal lobes plane or slightly convex, widely spreading, 

 ovate to orbicular, rounded at the apex, entire; lobule strongly inflated and 

 more or less contracted in the outer part, with a single apical tooth bearing 

 a hyaline papilla at its distal base; leaf-cells usually with distinct trigones. 

 Underleaves suborbicular, bifid, the divisions mostly acute and the margins 

 entire. Antheridia usually borne in pairs in the axils of saccate bracts, the 

 latter usually in short androecia. Archegonia borne singly on branches 

 variable in length, with or without subfloral innovations, the bracts with plane 

 and usually acute lobules; bracteoles bifid. Perianth compressed with sharp 

 lateral keels, often becoming two-lipped with age. Vegetative reproduction 

 by means of caducous leaves. [Greek, lipyed-Lejeunea.] About 60 species, 

 mostly tropical. Type species: C. aneogyna (Spruce) Evans. 



1. Cheilolejeunea decidua (Spruce) Evans, Bull. Torr. Club 33: 6. 1906. 



Lejeunea decidua Spruce, Trans. Bot. Soc. Edinb. 15 : 257. 1884. 



Pale or brownish green, growing in depressed mats. Leaves imbricated, 

 the dorsal lobe ovate, about 0.7 mm. long; lobule triangular ovate in outline, 

 apex tipped with a long, pointed, slightly curved cell; leaf -cells usually with 

 trigones but sometimes thin-walled throughout, averaging about 20 m; under- 

 leaves distant, plane, orbicular, bifid to the middle or less with triangular, 

 erect, sharp divisions -and a broad sinus. Inflorescence dioecious. Female in- 

 florescence borne on a short branch, with or without a subfloral innovation; 

 perianth broadly obovate; caducous leaves borne on prostrate branches. 



On logs, near NicholTs Town, Andros : Florida ; Cuba ; Forto Rico ; Brazil. De- 

 ciduous-leaved Cheilolejeunea. 



9. EUOSMOLEJEUNEA [Spruce] Sehiffn. in E. & P. Nat. 

 Pflf. I s : 124. 1894. 



Yellowish green and firm. Stems prostrate, often elongated, irregularly 

 branched, the branches as in Radula; rhizoids springing from the base of the 

 underleaves. Leaves complicate-bilobed, the dorsal lobes much larger than the 

 ventral, incubous, attached by a long line, broadly ovate, convex, rounded at 

 the apex, entire or nearly so; lobule strongly inflated, acute, bearing a hyaline 

 papilla in the sinus, at the base of the apical tooth; leaf-cells with conspicuous 

 trigones; ocelli none. Underleaves varying from medium-sized to large, some- 

 times imbricated, orbicular and often cordate at the base, usually bifid with an 

 acute to lunulate sinus, rarely undivided. Antheridia usually in pairs in the 

 axils of saccate bracts, the latter in more or less elongated androecia, often 

 proliferating. Female inflorescence borne on a more or less elongated branch, 

 with one or two subfloral innovations; bracts similar to the leaves but with 

 plane lobules and sometimes with pointed lobes; bracteole bifid, free. Perianth 

 often roughened by projecting cells, sharply 5-keeled, the keels rounded above, 

 beak distinct. Gemmae none. [Greek, fragrant Lejeunea.] About 35 species, 

 largely tropical. Type species: E. trifurm ( hVimv. Bl. & Xees) Sehiffn. 



Dioecious, perianths rarely present. 



Fnderleaves small and distant, narrowed inward base. 1. E. duriuacuUi. 



Underleaves large and usually overlapping, rounded to cor- 

 date at base. 2. E. elttuaa. 

 Autoeeious. perianths usually present : underleaves large ami 



usually overlapping, rounded to cordate at base. ''< I- 1 , trifaria. 



