250 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
P. balsamifera L., var. virginiana Sarg. Cottonwood; Neck- 
lace Poplar.— (P. deltoid cs Man. ed. 7 and 111. Fl. ed. 2.) 
Along .streams in the valley; frequent. 
P. grandidentata Michx. Large-toothed Aspen. — Woods; 
common. 
P. NIGRA L., var. ITALICA Du Roi. LOMBARDY PoPLAR. — {P. 
italica 111. Fl. ed. 2.) 
Oceasionally spreading from cultivated trees. 
P. tacamahacca Mill. Balsam Poplar. — (P. balsamifera Man. 
ed. 7 and 111. Fl. ed. 2; vid. Journ. Arnold Arb., 1: 61, 1919.) 
Spreading freely from planted trees. Indigenous along Cascade 
Brook, Hoosac Tunnel, Florida. 
var. Michauxiana (Dode) Henry. — River-bank, North Adams 
(Fernald and Long). 
Differs from the type in the ovate leaves with a broad, rounded or 
subcordate base, and slight pubescence on the midrib and veins be- 
neath; petioles and twigs are also slightly hairy. Vid. Garden 
Chronicle, ser. 3, 59: 230 (1916). 
P. tremuloides Michx. American Aspen. — Dry woods and 
clearings; common. 
SALIX. Willow. 
S. ALBA L. White Willow. — Along streams ; occasional. Deer- 
field R., Florida; Williamstown; Adams (Churchill); Pittsfield; 
Great Barrington; Egremont. 
var. vitellina (L.) Koch. — Along rivers and streams; common in 
the valley, occasional up to an altitude of 1500 feet on the plateau. 
S. Candida Flligge. Hoary Willow. — Cold bogs; frequent. 
var. denudata Anders. — ^Occasional. Stockbridge; West Stock- 
bridge (Evans, Fernald and Knowlton); Egremont. 
S. cordata Muhl. — Low ground, along streams and on the plateau, 
along roadsides; common. Summit of Greylock, 3500 feet. 
var. myricoides (Muhl.) Carey. — Occasional. October Mt., 
Washington; Pontoosuc Lake, Lanesboro (Churchill). 
S. discolor Muhl. Glaucous Willow; Pussy Willow. — 
Swamps and low ground, and on the plateau, along roadsides; com- 
mon. 
var. eriocephala (Michx.) Anders. — Occasional. Pittsfield. 
var. prinoides (Pursh) Anders. — Great Barrington. 
