164 PROCEEDINGS OF THE ACADEMY OF [March, 



reflexed closely appressed lobes; flesh thin, yellow-green, hard, juicy, 

 bitter and acidulous; nutlets, usually 2, acute at the apex, obtuse and 

 rounded at the base, ridged on the back, with a broad slightly grooved 

 ridge, 10-11 mm. long and 5-6 mm. wide. 



A tree 4-5 m. high, with a short trunk 1-1.5 dm. in diameter covered 

 with dark scaly bark, small spreading branches forming an open 

 irregular head, and stout only slightly zigzag branchlets dark orange- 

 green and marked by pale lenticels when they first appear, becoming 

 dark chestnut brown to bronze green and lustrous in their first season, 

 and dark gray-brown the following year, and armed with stout straight 

 or slightly curved chestnut brown spines 3.5-4 cm. long. 



Nine Mile Run, near Pittsburg, Allegheny County, O. E. Jennings, 

 (No. 7S type) May 27, 1907, O. E. and Grace K. Jennings, September 

 13, 1909. 



3. Pruinos.e. 



Leaves thick, generally broad at the base; petioles long, usually 

 slender; flowers large, in glabrous or hairy corymbs; stamens 

 5-20 ; anthers rose color or white. Fruit short-oblong, ovate or 

 obovate, often broader than high, frequently conspicuously angled, 

 green or red, generally pruinose, ripening late; flesh dry and hard, 

 the mature calyx prominent, raised on a short tube; nutlets 3-5. 

 Anthers rose color or pink. 

 Stamens 20. 



Leaves smooth on the upper surface. 

 Leaves blue-green. 

 Fruit not mammillate. 



Leaves rounded or abruptly cuneate at the base. 



Leaves ovate to oblong-ovate; fruit depressed-ovate, 

 conspicuously 5-angled; flesh tinged with red. 



1. C. angulata. 

 Leaves oblong-ovate; fruit obovate, not conspicuously 



angled 2. C. viatica. 



Leaves concave-cuneate at the base; fruit subglobose 



to short-oblong, 5-angled 3. C. wilmorensis. 



Fruit mamillate below the middle, conspicuously 5-angled. 



4. C. arcana. 

 Leaves yellow-green. 



Flowers in 8-12-flowered corymbs ; fruit oval to pyriform- 



oval 5. C. crawfordiana . 



Flowers in 4-7-flowered corymbs. 



Anthers pink; fruit obovate, deep orange-red. 



6. C. gaud ens. 

 Anthers dark rose color; fruit short-oblong, green. 



7. C. bellahda. 

 Leaves scabrate on the upper surface. 



