60 HEPATIC^. 



11. Lejeunea Rossettiana, Mussed. 



Lejeunea Rossettiana, Massalongo, Nuovo Giorn. Bot. Ital. vol. xxi. p. 487 

 (1889). 



Dioicous, intricately caespitose, minute, yellowish-green. 

 Stems subdicliotomoLis or subpinnate, more or less radiculose, 

 rootlets few, fasciculate, pale. Leaves imbricate, patent, 50°-60°, 

 bilobed, antical lobe somewhat convex, ovate, apices more or less 

 attenuate-acuminate (rarely only acute), usually incurved, upper 

 surface echinate, postical lobe about |- to ^ the size of the antical, 

 subquadrate to roundish-quadrate, tumid at the keel, upper 

 portion plane, margin not incurved, unequally dentate-spinulose, 

 exterior surface echinate like the antical lobe, texture opaque : 

 cells very minute, 4-, 5-, and 6-sided, walls distinct, no trigones 

 or thickened angles ; papillse conical, one to each cell. Stipules 

 absent. Stylus also wanting. Female flowers on short branches, 

 subtended by an innovation. Bracts similar to the leaves, only 

 larger, postical lobe with margin more finely dentate-spinulose. 

 Bracteole wanting. Perianth projecting more than half beyond 

 the bracts, oval to pyriform, upper portion obtusely 5 -angled, 

 epidermis rauricate. Androecia unknown. 



Dimensions. — Stems about \ of an inch long, "05 mm. 

 diameter, with leaves '85 mm.-l* mm. wide; leaves, antical lobe 

 •45 mm. x -25 mm., postical -225 mm. x "15 mm., antical -45 mm. 

 X "275 mm., postical "225 mm. x '15 mm.; cells -0125 mm.; 

 papillse "0125 mm. long x '01 mm. wide at the base ; bract, antical 

 lobe "5 mm. X -25 mm., postical '25 mm. x '15 mm.; perianth 

 •6 mm. X -45 mm., '55 m.m. x -4 mm. 



Obs. — Diflers from Lejeunea calcarea, Lib., with which it has 

 been confounded by British botanists in its dioicous inflorescence, 

 more opaque texture, slightly larger size, leaves a little more 

 spreading, echinate postical lobe, with margin more dentate- 

 spinulose, and not incurved, as in L. calcarea (the margin of which 

 cannot be seen without dissection), and by the entire absence of 

 the styliform appendage, usually found between the stem and the 

 leaf of L. calcarea. The above mentioned characters show this 



