wp nag 
> 
BOTANY. 161 
as a general resemblance to A. rigidum, Sw. The soriare as large as in A. marginale. 
When young, the stipe and rachis are thickly clothed with chaffy scales. 
ASPIDIUM ACULEATUM, Swartz; Hook. Fl. Bor. Am. 2, p. 261; Torr. Fl. N. York, 2, p. 498. 
Deep ravines, Napa Valley, California. Some of our specimens agree better with A. lobatum 
than with A. aculeatum ; but we fully agree with Hooker, that these and A. angulare con- 
stitute but one species. Kating thinks that a part, at least, of the North American forms of 
A. aculeatum should be referred to A. (Polystichum) Braunii, Spenn. Fl. Frib. 
SALVINIACE2. 
AzoLLA CAROLINIANA, Willd. Sp. 5, p. 541; Torr. Fl. N. York, 2, p. 513. A. microphylla, 
Kaulf.; Hook. de Arn. Bot. Beech. p. 162. On the surface of slow-flowing or stagnant waters, 
Western New Mexico and California. 
21+ 
