SCAPANIA 153 
thinner, softer, less decurrent leaves, with nearly orbicular lobes, 
of which the convex dorsal is 4-1; the size of the ventral and 
sharply pointed, the ventral commonly with a short point. 
5. SCAPANIA UMBROSA (Schrad.) Dumort. Rec. d'Obs. Jung. 14. 
1835. 
Jungermannia umbrosa Schrad. Syst. Samml. Krypt. Сем. 2: 
5. 1797. Schrad. Jour. Bot. 1801: 67. 1803. Hook. Brit. 
Jung. A. 24. 1816. 
Jungermannia convexa Scop. (?) Fl. Carn. 2: 349. 1772. 
[24 ед. | 
Martinellia convexa Lindb. Musc. Scand. 6. 1870. 
Scapania convexa Pearson, List Can. Hep. 15. 1890. 
Yellowish-green to brown, sometimes tinged with purple, in an 
extended, closely appressed, usually compact stratum : stems 5-15 
mm. long, branching or subsimple, ascending, decurved at apex es- 
pecially when dry : leaves increasing somewhat in size upward, not 
decurrent, bilobed 14—24 their length, the fold rounded or acute, 
sometimes with a trace of a winged keel; ventral lobes 2—3 times 
larger than the dorsal, oblong-ovate, acute or subacuminate, ir- 
regularly serrate-dentate toward apex, deflexed and often some- 
what secund; dorsal lobes ovate, acute, sometimes narrowly 
pointed, dentate, nearly parallel to the stem, appressed-imbricate, 
except in slender sterile conditions : leaf-cells small, roundish-oval, 
12-27 и, more elongated toward base, thick-walled, trigones dis- 
tinct, cuticle minutely roughened : gemmae in dark-brown clusters 
at stem-apex, mostly uniseptate, oblong-elliptical, 18 x 9 и: dioi- 
cous: androecium terminal, antheridia 1-3 in axils of smaller, 
х.6-1 mm., twice as long ав the involucral leaves, often 
purple at base, compressed, mouth entire or repand: capsule oval- 
oblong, dark-brown, long-exserted ; spores brown, punctulate, 
тои; elaters 125-165 их 7-8 pt. 
Exsicc. Hep. Am. 101. 
On old logs beside shaded streams, North Fork of the Little 
River, Mendocino Co. (647, 683) and Eureka, Humboldt Co. 
(961) ; also on compact argillaceous soil in the first-named locality 
(686). Хо. 711, from a log in Russian Gulch, near Mendocino, 
which we formerly (Erythea 5: 89. 1897) referred to Scapania 
glaucocephala, we now believe to be ап abortive, gemmiferous con- 
