1905.] NATURAL SCIENCES OF PHILADELPHIA. 601 



17. Crataegus dissona Sargent. 



Rhodora, V, 60 (1903); Bot. Gazette, XXXV, 379 (Cratsegus in Northeast- 

 ern Illinois). 



Bucks county: Race-bank, Benjamin, near Sellersville, C. D. Fretz 

 (No. 106), May and September, 1899; Fretz and Sargent, September, 

 1902. Also western New England to northeastern Illinois. 



The anthers of the plants at Great Barrington, Berkshire county, 

 Massachusetts, on which this species was established, are light purple, 

 while those of the Sellersville plant are described by Dr. Fretz as light 

 pink. I can detect no other difference. This shrub is evidently ex- 

 tremely rare in eastern Pennsylvania, while in western New England 

 it is common and widely distributed. 



18. Crataegus alacris n. sp. 



Leaves rhombic or occasionally oblong-ovate, acuminate, mostly entire 

 at the cuneate glandular base, sharply doubly serrate above, with straight 

 glandvilar teeth, and deeply divided above the middle into numerous 

 narrow acuminate lobes, dull vinous red as they unfold, nearly fully 

 grown when the flowers open about the middle of May and then light 

 yellow-green and glabrous with the exception of a few caducous hairs 

 near the base of the upper side of the midribs, and at maturity thin but 

 firm in texture, glabrous, dark blue-green on the upper and pale blue- 

 green on the lower surface, 4-6 cm. long and 3.5-4.5 cm. wide, with thin 

 yellow midribs, and slender primary veins arching very obliquely to the 

 points of the lobes; petioles slender, slightly wing-margined at the 

 apex, sparingly glandular early in the season, with minute deciduous 

 glands, and 2-3 cm. in length; stipules linear, acuminate, glandular, 

 fading pink, caducous, or foliaceous and lunate on the upper leaves of 

 leading shoots. Flowers 1.8-2 cm. in diameter, on slender elongated 

 glabrous pedicels, in usually 5-flowered glabrous corymbs, with oblong- 

 obovate to linear glandular caducous bracts and bractlets ; calyx-tube 

 narrowly obconic, the lobes broad and short, gradually narrowed to the 

 acuminate apex, entire, occasionally slightly serrate above the middle; 

 stamens 8-10; anthers pale rose color; styles 3 or 4, surrounded at the 

 base by a broad ring of long white hairs. Fruit ripening at the end of 

 September, on slender pedicels, in drooping clusters, short-oblong or 

 slightly obovate, bright red and covered with a glabrous bloom, 1-1.2 

 cm. long, 8-10 mm. broad; calyx prominent, with a wide but very 

 shallow cavity, and spreading lobes, their tips mostly deciduous from the 

 ripe fruit; flesh thin, dry and mealy; nutlets 3 or 4, rounded at the 

 narrowed base, acute at the apex, prominently ridged on the back, with 

 a broad deeply grooved ridge, 6-7 mm. long and 4-5 mm. wide. 



