190 
places of central Montana. Spanish Basin, collected by J. H. 
Flodman (no. 362), and by myself in 1895, near Mystic Lake, no, 
2609. _ 
v ALNUS sINuATA (E. Regel). 
Alnus viridis 8 Hook. Fl. Bor. Am. 2: 157. 1837. 
Alnus viridis sinuata E. Regel in DC. Prod. 16: Part 2, 183. 
1868. 
Shrub 1-5 m. high; young bark brown and glossy with scat- 
tered white lenticels; older bark grayish; leaves 3-10 cm. long, 
oval, acute or acuminate at both ends, sinuately lobed and doubly 
and sharply serrate, thin, green and glabrous on both sides, very 
glutinous when young, in age shining ; peduncles racemiform, very 
warty; staminate catkins 2 cm. long, sessile; pistillate ones 
shortly ellipsoid, 8-1o mm. long and 6-7 mm. in diameter, on 
pedicels 3-15 mm. long. 
It most resembles A. vzridis, but is easily distinguished by the 
thinner, more shining leaves, which are always more or less lobed © 
and quite without any development of pubescence. In A. viridis, the 
veins on the lower surface are more or less ferruginously puberu- _ 
lent. In the same species the pistillate catkins are generally over 
Icm.long. A. sézuata has also been confounded with A. éenut- 
folia Nutt., which, according to Sargent, is an older name for A. 
incana glauca Regel or A. tncana virescens Wats. I have not ac- 
cess to Nuttall’s Sylva and am not able to verify this point. In the 
plate of A. ¢enuifolia in the Silva of North America, the leaves re- 
semble more the present species than A. ixcana glauca, but Prof. 
Sargent’s description and synonomy belongs evidently to the lat- 
ter. In A. tenuifolia,i. e., A. incana glauca, the leaves have much» 
rounder lobes and less shay dentations, are less acuminate, thicker, 
and generally somewhat pubescent on the veins. The pistillate 
catkins are, as a rule, nearly sessile on the common peduncle. 
It is fairly common in the mountain regions of Montana. 
(Flodman, no. 369, Spanish Basin, July 10,1896.) In the Colum- 
bia herbarium there are three specimens of this species, viz.: one 
collected by Mertens at Sitcha, one by Scouler (no. 59) from the 
Columbia, and one received from Hooker, but without any in- 
dication of collector or locality. Probably it was seected by 
Douglas. . 
