NORTH AMERICAN SPECIES OF CEANOTHUS. 117 



The fruit of prostratus is usually considerably longer than 

 broad, about 8 mm. in diameter, ratiier fleshy, with 3 nearly 

 erect prominent horns, and an accessory set of apical crests 

 or smaller horns. 



Cuneatiis produces subglobose or very slightly elongated 

 fruit, about 6 mm. in diameter, with thin flesh, and usually 

 3 rather small horns, an accessory set of smaller ones being 

 occasionally seen. 



0. Greggli, closely related to cuneatus, is marked by its 

 leaves, often white - tomentose below, mostly equally 

 rounded and acute at both ends, frequently with one or two 

 small teeth on either side, and its rather pointed fruit, 

 about 4 mm. in diameter, seemingly nearly or quite horn- 

 less, the white calyx-lobes more persistent than usual. 



C. crassifolius, as it is now accepted, is very heterogen- 

 eous, embracing plants with entire or toothed smooth green 

 leaves, and others with the leaves pungently toothed, revo- 

 lute margined, and very white-woolly below. The fruit is 

 as much as 8 or 10 mm. in diameter, depressed-globose, 

 smooth or with 3 low deeply dorsal horns, and the base (in- 

 vested by the adnate calyx) very prominent, and indurated. 

 The leaves are always firm and thick. 



C. rigidas has thinner, often cuneate-obcordate, mostly 

 denticulate leaves, and blue or purplish flowers. Good fruit 

 is desirable. Some specimens suggest hybridization with 

 C. prostratus. 



C. verrucosus is very similar to rigidus in its foliage char- 

 acters, but with slender twigs, alternate leaves and white 

 flowers. The figure of rigidus in Bot. Mex. Bound, pi. 9, 

 is evidently this species. Its fruit is mostly 4 to 6 mm. in 

 diameter, with small dorsal horns, or none. 



