114 ROCHESTER ACADEMY OF SCIENCE. 



does not ripen until the end of September or the beginning of October 

 and then soon falls. 



Rochester ; banks of the Genesee River, Genesee Valley Park, 

 JoJin Dunbar^ May, August and September, 1901, October 9, 1902, 

 C. S. Sargent, September 29, J902. 



§ DILATATAE. 



Fruit medium size to large, subglobose, scarlet ; fruit-calyx much 

 €7ilarged, the lobes dark red ofi the upper side toward the base ; 

 nutlets 5, ridged on the back; corymbs few or many-floivered ; 

 stamens 20 ; anthers rose color ; leaves membranaceo2is, on vigorous 

 shoots as broad or broader than long. 



Leaves ovate ; corymbs many-fiowered, glabrous ; fruit 

 medium size, persistent until winter. 



18. C. Durobrivensis, 



Crataegus Durobrivensis, Sargent, Trees and Shrubs, i. 3, t. 2 

 (1902). 



Rochester ; steep banks of the Genesee River north of the city ; 

 banks of the Niagara River, Niagara Falls, New York, C. S. Sargent, 

 September, 1901 ; Buffalo, New York, foJin Dunbar, September, 1901. 



§ LOBULATAE. 



Fruit large, oblong, scarlet ; n2itlets j-^, prominently grooved or some- 

 times ridged on the back ; corymbs many-flou'ered, glabrous or 

 villose ; stamens 5-10; anthers rose color; leaves large, mem- 

 branaceous. 



Leaves oval to ovate, light yellow-green ; corymbs sparingly 

 villose or glabrous ; stamens usually 5 ; nutlets 3. 



Tg. C. Holmesiana. 



Leaves ovate-oblong, dark yellow-green ; corymbs densely 



villose; stamens usually 5 ; nutlets 5. 20. C. acclivis. 



Leaves broadly ovate to oval, dark green; corymbs slightly 



villose ; stamens 10 ; nutlets 2. 21. C. pedicellata. 



Crataegus Holmesiana, Ashe, four. Elisha Mitchell Sci. Soc. xvi. 

 pt. ii. 78 (1900). Sargent, Bot. Gazette, xxxi. 10; Silva N. 

 Am. xiii. 119, t. 676. 



This species as it grows at Rochester and is common near Toronto 

 and in the neighborhood of Montreal differs from Crataegus Holmesiana 



