JUNGEKMANNIACEAE. 519 



with revolute apex and lower margin; lobule sometimes blunt at the apex and 

 sometimes with a more or less elongated acuminate tooth, reaching a maximum 

 length of four cells, not visible without dissection; leaf-cells averaging 

 about 20 ix. 



On bark, New Providence : Florida ; widely distributed in the American trop- 

 ics ; Africa ; Java. Yellow-fbuited Leucolejeunea. 



19. FRULLANIA Eaddi, Atti Soc. Ital. Sci. Modena 18: 20. 1818. 



Dark green or more or less pigmented with yellow, brown or red. Stems 

 prostrate, ascending or pendent, more or less copiously branched, the branches 

 all arising at the bases of leaves without lobules, rhizoids springing from the 

 bases of the underleaves. Leaves deeply complicate-bilobed, the dorsal lobes 

 much larger than the ventral, incubous, widely spreading, ovate to orbicular, 

 usually entire, lobule normally inflated, helmet-shaped; leaf-cells with distinct 

 trigones; ocelli present in certain species. Underleaves smaller than the leaves, 

 usually bifid. Antheridia mostly in pairs, in the axils of inflated bracts with 

 explanate lobules, the bracts imbricated and forming short or more or less elon- 

 gated androecia. Female inflorescence borne on a more or less elongated, 

 branch, without innovations; bracts larger than the leaves, with explanate 

 lobules and often more or less connate with the bifid bracteole. Perianth nor- 

 mally 3-keeled, with one keel ventral, but often with supplementary folds, ab- 

 ruptly contracted into a short tubular beak. [Commemorates L. Frullani, a 

 Florentine minister of state.] A very large genus, 800 or more described spe- 

 cies, mostly tropical. Type species: F. dilatata (L.) Dumort. 



Leaves not squarrose. 



Perianth with two lateral keels and a two-angled ventral keel ; lobule inflated in 

 upper part only. 

 Paroecious. 1. F. arietina. 



Autoecious. 2. F. riojancircnsls. 



Perianth distinctly three-keeled ; lobule inflated throughout. 5. F. obcordata. 

 Leaves more or less squarrose when moist. 



Perianth with two lateral keels and a two-angled ventral 



keel, surface smooth. 3. F. gibbosa. 



Perianth distinctly three-keeled, the surface roughened by 



scattered tubercles or scales. 4. F. squarro&a. 



1. Frullania arietina Tayl. in G. L. & N. Syn. Hep. 413. 1845. 



Bright green, yellowish green or brownish green, scattered or in loose tufts. 

 Leaves imbricated, the dorsal lobe plane or nearly so, orbicular-ovate, about 1.2 

 mm. long; lobule inflated in the upper part only, the lower forming a subrhom- 

 boidal expansion; leaf -cells with conspicuous trigones, averaging about 30/*; 

 underleaves orbicular, shortly bifid, entire or nearly so; inflorescence paroecious, 

 the saccate male bracts in two or three pairs below the female inflorescence; the 

 latter borne on a short branch ; bracts in one to three pairs, the innermost w ith 

 ovate, acute, sparingly toothed lobes and similar but narrower lobules ; bracteoles 

 highly connate, bifid with narrow, sharp divisions; perianth oblong with two 



distinct lateral keels and a broad two-angled ventral keel. 



On twigs, Grantstown, New Providence : Florida ; widely distributed in trop- 

 ical America. Ram's Head Fkullania. 



