04 JUNGERMANNIACEAE 
Key to the Species. 
Stems 3-8 mm. long, .15-.35 mm. in diameter, root-hairs colorless or yellowish ; leaves 
4-1.3 mm. long, usually broader than long, margined by enlarged cells or immar- 
ginate, slightly or not at all decurrent, median and superior leaf-cells 25-40; 9 
bracts more or less adnate to perianth at its extreme base. І. N. crenulata. 
Stems 10-20 mm. long, .27-.64 mm. in diameter, root-hairs reddish-purple (occasionally 
decolorate); leaves .9-1.7 mm, long, usually longer than broad, mostly patent-hori- 
ontal and but slightly overlapping, obscurely if at all margined, decurrent, median 
and superior leaf-cells 32-60 и; the inner Ф bracts adnate to perianth for two thirds 
its length. . М. obovata. 
т. NARDIA CRENULATA (Sm.) Lindb. Act. Soc. Sci. Fenn. 10: 529. 
1875. | 
Jungermannia crenulata Sm. Eng. Bot. pl. 1463. 1805. Hook. 
Brit. Jung. pl. 37. 1816. | 
Jungermannia gracillima Sm. Eng. Bot. M. 2238. 1811. 
Jungermannia. crenulata gracillima Hook. Brit. Jung. f. 37. 
1816. 
Jungermannia Genthiana Hiiben. Hepaticol. Germ. 107. 1834. 
Nardia gracillima Lindb. Act. Soc. Sci. Fenn. 10: 530. 1875. 
Мага crenulata gracillima Lindb. Musc. Scand. 8. 1879. 
Jungermannia rubra Gottsche; Underw. Bot. Gaz. 13: 113: 
pl. 4. 1888. Bolander, Cal. Med. Gaz. 1870: 184 (40) (name 
only). 1870. 
ent, 
cent ; cuticle irregular and minutely hyaline-punctate : underleave> 
Мета ог very rarely present in association with the 9 E 
„01005 : androecium terminal, 3 bracts 3—10 pairs, concavo mi. 
gined, suberect, imbricate ; antheridia usually іп pairs, glo 
