1905.] NATURAL SCIENCES OF PHILADELPHIA. 579 



2.— Nutlets with longitudinal cavities on their ventral faces ; fruit pyri- 

 form to subglobose or short-oblong, 1-1.5 cm. in diameter 

 lustrous, orange or scarlet; nutlets 2 or 3, usually obtuse at 

 the ends, prominently ridged on the back, 10. Tomentos.^. 



I.— CRUS-GALLI. 



Anthers rose color. 



Primary veins within the parenchyma; leaves obovate-cuneiform. 

 mostly rounded at the apex; stamens 10; fruit short-oblong, 

 often covered with a glaucous bloom, 8-12 mm. long; nutlets 2, 



1. C. crus-galli. 

 Primary veins without the parenchyma, thin but conspicuous. 

 Leaves obovate to oval, acute at the apex; stamens 15, fruit short- 

 oblong, dull red covered with a glaucous bloom, 1.8-1.2 cm. 



long;°nutlets 2, 2. C.rivalis. 



Leaves oblong, cuneate to ovate or rarely obovate, acute or rarely 

 rounded at the apex; stamens 10-13; fruit short-oblong to 

 subglobose, dark crimson, lustrous, 1.2-1.5 cm. long; nutlets 

 3_5 3. C. canbyi. 



Anthers pale yellow. 



Leaves obovate, acute, acuminate or rarely rounded at the apex, 

 their primary veins mostly within the parenchyma; stamens 

 5-10, rarely 12; fruit short-oblong, 1-1.2 cm. long, dark dull 



crimson; nutlets lor 2, i. C. arduenme. 



Leaves obovate-cuneate, short-pointed or rarely rounded at the apex, 

 their primary veins very slender, mostly without the paren- 

 chyma; stamens 8-10; fruit subglobose, dark crimson, rather 

 lustrous, 8-9 mm. in diameter; nutlets 1 or 2, 5. C. hartramiana. 



1. Crataegus crus-galli Linnaeus. 



Spec. 476 (1753). Sargent, Silva N. Am., IV, 91, t. 178; Man. 368, 



Cratcegus trahax Ashe, Jour. Elisha Mitchell Sci. Soc, XIX, part I, p.^27 



(1903). Gruber, Proc. Berks County Nat. Sci. Club, I, 21 (Cratajgusjin 



Berks County, II). 



Berks county: North Heidelberg, C. L. Gruber (No. 61), 1901, May 



and September, 1903; (No. 105), 1902, May and August, 1903; Kutz- 



town, C. L. Gruber (No. 45), 1902, August, 1903. Philadelphia county : 



Gray's Ferry, Philadelphia, A. MacElwee{No. 2,267, Herb. Philadelphia 



Museums), June, 1901; Haddington, A. MacElwee (No. 2,233A, Herb. 



Philadelphia Museums), June, 1901. 



Crakegus trahax (Gruber, No. 45) appears to differ from common 

 forms of Cratcegus crus-galli only in its usually unarmed branchlets and 

 small fruit. Gruber's No. 105 is, perhaps, the same. 



Crataegus crus-galli var. oblongata Sargent. 



Bot. Gazette, XXXV, 99 (The Genus Crakegus in New Castle County, Dela- 

 ware); Man. 369. 

 Leaves slightly hairy on the upper side of the midribs while young, 



