78 HEPATIC^. 



7. Radula complanata [L.), Dum. 



Jungermania complanata, Linn. Sp. PI. 1599 (1753); Hook. Brit. Jung. t. 81 



(1816). 

 Radula complanata, Dum. Comm. p. 112 (1822). 



Paroicous, imbricately, widely, and shallowly csespitose, largish, 

 pale yellowish-green colour. Stems creeping, stratiose, subpinnate, 

 cortical cells about 35, similar in size to inner, only with thicker 

 walls, cells 8 x 10 in diameter; slightly radiculose, rootlets dirty 

 white, produced from postical side of postical lobes of leaves. 

 Leaves imbricate, patent to patent-divergent, 60°, unequally 

 bilobed, quite entire or erose, antical lobe roundish, slightly convex, 

 covering the stem, postical lobe about ^ smaller, quadrate, angle 

 obtuse or subacute, sometimes arcuate ; cells smallish-medium 

 size, hexagonal, walls thin, trigones very small, lumen full of 

 chlorophyll granules. Bracts similar in size to the leaves, antical 

 lobe elongato-obovate, postical lobe about half the size, ovate, apex 

 rotundate. Perianth projecting about half beyond the bracts, 

 obconical, complanate, mouth wide, truncate, quite entire. Capsule 

 dark brown, oval ; spores large, about 3 times the diameter of the 

 elaters, which are bispiral. Perigonial bracts 3-5 pairs, imme- 

 diately below the perianth (or on a lateral branch produced from 

 below it at the apex of which is always an imperfect female flower), 

 closely imbricate, erect or erecto-patent, tumid, unequally bilobed, 

 antical lobe oval, postical about half the size ; antheridia single, 

 globose. 



Gemmiparous, gemmae discoid, on the margins of leaves, 

 rendering them often irregular and erose. 



Dimensions. — Stems 1 to 2 inches long, diameter "15 mm., with 

 leaves 225 mm. to 2*5 mm. wide: leaves, antical lobe I'S mm. x 

 1"1 mm., postical lobe "7 mm. x '5 mm.; cells '035 mm. x "025 

 mm. ; innermost and perigonial bracts, antical lobe 1'12 mm. x "82 

 mm. ; postical 7"5 mm. x 5'5 mm. ; perianth 3* mm. x 1*25 mm. j 

 capsule 1"25 mm. x '75 mm. ; spores "03 ram. ; elaters, '2 mm. x 

 01 mm. ; antheridia 2 '25 mm' x '2 mm. 



Hab. — On the bark of trees. Common. 1 to 1 7. I. 



