464 



JUNGERMANNIACEAE. 



10. LEJEUNEA Libert. 



iStems prostrate, small, irregularly branched, the branches as in Badula; 

 rhizoids springing from the bases of the underleaves. Leaves complicate- 

 bilobed, the dorsal lobes larger than the ventral, incubous, attached by a long, 

 almost longitudinal line, plane or convex, widely spreading, ovate to obovate, 

 rounded to obtuse at the apex, entire or slightly crenulate; lobule when well 

 developed inflated, acute, bearing a hyaline papilla at the base of the apical 

 tooth on the side next to the stem; leaf-cells thin-walled but sometimes with 

 small trigones. Underleaves ovate to orbicular, bifid, the division mostly entire 

 or crenulate. Antheridia borne singly or in pairs in the axils of saccate bracts, 

 the latter in more or less elongated androecia. Archegonia borne singly on 

 branches variable in length with one or two subfloral innovations, the bracts 

 with plane lobules, bracteole bifid. Perianth inflated, 5-keeled, abruptly nar- 

 rowed to a distinct tubular beak. [Commemorates A. L. S. Lejeune, Belgian 

 botanist.] Nearly 200 species, mostly tropical. Type species: L. cavi folia 

 (Ehrh.) Lindb. 



1. Lejeunea minutiloba Evans. Small- 

 LOBED Lejeunea. (Fig. 512.) Bright or 

 pale green, loosely tufted or mixed with 

 other plants. Leaves contiguous or slightly 

 imbricated, the lobe ovate, about 3" long, 

 rounded at the apex, entire or nearly so; 

 lobule represented by a minute, basal fold; 

 leaf-cells thin-walled, with scarcely evident 

 trigones ; underleaves distant, orbicular, bifid 

 about one third with broad, rounded or 

 bluntly pointed lobes and a narrow sinus, 

 slightly crenulate on the margins; inflores- 

 cence autoecious ; female inflorescence borne 

 on a long or short branch with a single inno- 

 vation; bracts shorter than the leaves; brac- 

 teole sharply bifid with obtuse to rounded 

 divisions; perianth obovate in outline, 5- 

 keeled in the upper part. 



On stones, rocks, and trees, Church Cave 

 and vicinity, 1900, M. A. Howe 7; 1908, 8. 

 Brown, 50!,, 505 \ 1912, E. a. Britton 1088: 

 Walsingham, 1900, M. A. Hone 3; 1905. E. G. 

 Britton 2S6 ; Tuckerstown, 1905, E. O. Britton 

 323: 1908. 8. Brown 516: Abbot's Cliff, 1912, 

 1913, E. G. Britton 8S8, 931, 932 (in part), 933, 

 1867: without definite locality, 1908, S. Brown 

 559a. West Indies. Previously listed from 

 Bermuda as L. glaucescens Gottsche. 



11, RECTOLEJEUNEA Evans. 



Differs primarily from Lejeunea in its flattened perianth with sharp 

 lateral keels. Dorsal lobes, lobules and underleaves similar, but the lobes 

 commonly broader; ocelli sometimes present among the leaf-cells. [Greek, 



