30 
WHITE ALDER. 
ALNUS inc ana; foliis oblongis acutis subtus pubescentibus, 
axillis venarum nudis, stipulis lanceolatis. Willd. Sp. pi. 
Mnus undulata, Willd. Sp. pi., vol. 4. p. 336. 
Black Alder, ( Mnus glauca,) Mich. Sylva, vol. 1. p. 378. 
Betula Mnus, crispa, Mich. Flor. Bor. Am., vol. 2. p. 181. 
j Betula crispa , Aiton. Kew., vol. 3. p. 339. 
Betula alnus, p. Linn. Sp. pi. 
This species forms a much smaller tree than the 
common Alder, being only 12 to 18 feet high, and 
sometimes indeed a mere shrub, as in the Alleghany 
Mountains in Pennsylvania. In Massachusetts and 
Maine it attains its greatest size. Its bark is grey or 
cinereous; the leaves are sometimes villous beneath, 
and the stipules persistent after the development of the 
leaves, which are no way glutinous; those of the young 
plants are smooth and glaucous beneath. It is common 
to the mountainous parts of Europe nor less than to the 
northern parts of the United States- It occurs likewise 
in this vicinity. 
MOUNTAIN ALDER. • 
ALNUS viridis, (Decandolle;) foliis rotundato-ovatis ir- 
regulariter argute serratis glabriusculis, stipulis ovatis 
membranaceis deciduis; fructibus late alatis. 
Mnus viridis, Decandolle, Flore Frangaise, vol. 3. p. 304. 
Betula viridis, Villars, Dauphin, vol. 4. p. 789. 
Betula ovata, Schrank, Salisb. p. 25. 
