62 BULLETIISr 119, U, S. DEPARTMENT OF AGRICULTURE. 



flower clusters, but this appears to be a variable character both in 

 the species and subspecies. The earliest name is therefore used to 

 designate the low western form which occurs from Fort McMurray, 

 in about latitude 57°, Alberta, southward along the eastern slope of 

 the Rocky Mountains to central Colorado. 



The proposed species Cerasus tricJiopetala was based on a flowering 

 specimen collected by R. S. Williams, at Columbia Falls, Mont., 

 May 24, 1894. The specimen differs in no way from other material 

 of the subspecies. Prunus conjmhulosd was described from the 

 Bridger Mountains and the Little Rocky Mountains, Mont. 



Prunus Emarginata (Dougl.) Walp. 



Cerasus emarginata Dougl., 1834, in Hook. Fl. Bor. Amer., v. 1, p. 169. 



Prunus emarginata Walp., 1843, Repert. Bot., t. 2, p. 9. 



Cerasus glandulosa Kellogg, 1854, in Bui. Cal. Acad. Sci., v. 1, p. 59. 



Cerasus californica Greene, 1891, Fl. Franc, [pt.] 1, p. 50. 



Cerasus crenulata Greene, 1905, in Proc. Biol. Soc. Wash., v. 18, p. 56. • 



Cerasus arida Greene, 1905, in Proc. Biol. Soc. Wash., v. 18, p. 57. 



Cerasus prunifolia Greene, 1905, in Proc. Biol. Soc. Wash., v. 18, p. 57. 



Cerasus rhamnoides Greene, 1905, in Proc. Biol. Soc. Wash., v. 18, p. 58. 



Cerasus kelloggiana Greene, 1905, in Proc. Biol. Soc. Wash., v. 18, p. 58. 



Cerasus padifolia Greene, 1905, in Proc. Biol. Soc. Wash., v. 18, p. 59. 



Cerasus obliqua Greene, 1905, in Proc. Biol. Soc. Wash., v. 18, p. 59. 



Cerasus parvifolia Greene, 1905, in Proc. Biol. Soc. Wash., v. 18, p. 59. 



Cerasus obtusata Greene, 1905, in Proc. Biol. Soc. Wash., v. 18, p. 60. 



Prunus prunifolia Shafer, 1908, in Britt. and Shaf., N. Amer. Trees, p. 500. 



Leaves oblong-oval, obovate, or sometimes lanceolate (PL VI, 

 fig. 3), 3 to 5.5 cm. long, 1 to 2 cm. broad, narrowed or even cuneate 

 toward the base and obtuse or sometimes acute at the apex, the margins 

 serrate and the teeth tipped with minute, pointed, sometimes in- 

 curved glands, the base furnished with two or more larger dark- 

 colored glands, or sometimes eglandular, more or less pubescent as 

 they unfold, the upper surface at maturity green and glabrous, the 

 lower pale and glabrous or marked with a few scattered hairs; petioles 

 5 to 9 mm. long, glabrous or pubescent with short hairs; stipules 

 lanceolate and glandular serrate. Flowers 10 to 15 mm. broad, ap- 

 pearing with the leaves from early in April to the middle of June, 

 according to the locality and altitude, in corymbose clusters of 5 

 to 10; the pedicels subtended by small foliaceous dentate or laciniate 

 bracts 6 to 14 mm. long, glabrous or nearly so; calyx glabrous, cam- 

 panulate, the tube about 3.5 mm. long, the oblong or ovate-oblong 

 obtuse lobes slightly shorter; petals obovate, entire or erose, 4 to 5. 

 mm. long, glabrous or sparingly hairy on the outer surface toward 

 the base. Fruit globose, 8 to 10 mm. in diameter, ripening from 

 July to the end of September, bright red in color when first fully 

 grown, changing to nearly black when ripe, flesh thin, bitter, and 

 astringent; stone oval or slightly ovoid (PL XII, figs. 38 to 40), 



