HOFFMANN: FLORA OF BERKSHIRE COUNTY. 279 



A hybrid between T. cordifolia and Mitella diphyJla has been col- 

 lected in Williamstown by Sanborn Tenney (vid. Rhodora, 8: 91, 

 1906). 



HAMAMELIDACEAE. WITCH-HAZEL FAMILY. 



HAMAMELIS. Witch-hazel. 



H. virginiana L. Witch-hazel. — Woods; common in the val- 

 ley, becoming rare on the plateau. Reaches an altitude of 2000 feet 

 in Savoy. 



PLATANACEAE. PLANE TREE FAMILY. 



PLATAN US. Sycamore; Buttonwood; Plane Tree. 



P. occidentalis L. Sycamore; Buttonwood. — Flood-plains; 

 common in the valley. 



ROSACEAE. ROSE FAMILY. 



AGRIMONIA. Agrimony. 



A. gryposepala Wallr. — Open woods, clearings and roadside 

 thickets; common. 



A. striata Michx. — Low ground and moist open woods; common. 



AMELANCHIER. Siiadbush; Ju'neberry; Service Berry. 



Key to Amelanckier. 

 a. Flowens racemose. 



h. Teeth of the leaves coarse (on average leaves 3 to 5 (6) per cm.); veins 

 conspicuous, usually straight, parallel and close together; leaves oval 

 to oval-oblong, rarely orbicular; scrawny, slender, often arching 



shrub of a few rocky mountain-tops A. snnguincn. 



b'. Teeth of the leaves fine (5 to 12 per cm. on average leaves) ; veins irregu- 

 lar, unequally distant, usually with frociuent intermediate shorter ones. 

 c. Leaves denselj^ white-tomontose wlicn young, becoming green; lower 

 pedicels 7 to 18 mm. long, in fruit 10 to 25 mm. long. 

 d. Leaves rounded at the apex; petals short, 7 to 9 mm. long; 3 to 12 

 dm. high; stiffly upright shrubs forming patches. Shrub of 

 rocky mountain-tops or sandy plains in the .southern part of the 



valley t . slolonifera. 



d'. Leaves short acuminate, jietals usually elongated, 10 to 14 mm. long. 

 Flowers appearing very early, visually before the leaves. Shrub 

 or tree, generally solitary, or few together, widely distributed. 



A. canadensis. 



