BUCKTHORN FAMILY 75 



Leaves alternate, usually rather crowded, 5-15 mm. long, suborbicular to cuneate-obovate, retuse 

 to subcordate at apex, obtuse or rounded at base, thick and firm, plane, entire or shallowly 

 toothed, dark green and glabrous above, minutely canescent beneath ; flowers corymbose on short 

 axillary peduncles, white ; capsules 5 mm. broad, very shallowly lobed, laterally horned and ob- 

 scurely crested at apex. 



Dry hillsides and mesas, mainly Lower Sonoran Zone; western San Diego County, California, and adjacent 

 Lower California. Type locality: San Diego. March-April. 



28. Ceanothus crassifolius Torr. Hoary-leaved Ceanothus. Fig. 3138. 



Ccanothits crassifolius Torr. Pacif. R. Rep. 4: 75. 1857. 



Ceanothus verrucosus var. crassifolius K. Brandg. Proc. Calif. Acad. IL 4:208. 1894. 



Rigidly branched shrub, 2—3 m. high, with stout canescent or rusty tomentose branches. 

 Leaves opposite, 1.5-3 cm. long, elliptic-obovate, obtuse or rounded at apex, cuneate or rounded 

 at base, thick and leathery, more or less revolute, pungently dentate or rarely entire, becoming 

 glabrous and dark green or yellowish green above, densely white-tomentose beneath; stipules 

 large ; flowers white in short umbellate corymbs ; capsule 8 mm. broad, with stout erect horns 

 near the apex. 



Dry mountain slopes and hillsides, Upper Sonoran Zone; common component of the chaparral from Santa 

 ■Ra'-bara County, California, to northern Lower California. Type locality: "Mountains south of Los Angeles." 

 Feb.-April. 



Ceanothus crassifolius var. planus Abrams, Bull. N.Y. Bot. Card. 6: 415. 1910. This variety closely 

 resembles the typical species in structural characters, but the leaves are not revolute and the venation is dis- 

 tinctly evident through the rather sparse tomentvmi. This is the more common form of the species in the moun- 

 tains of Santa Barbara and Ventura Counties, California. Type locality: Red Reef Canyon, Topatopa Mountains, 

 Ventura County. 



29. Ceanothus vestitus Greene. Mojave Ceanothus. Fig. 3139. 



Ceanothus vestitus Greene, Pittonia 2: 101. 1890. 



Ceanothus Greggii var. vestitus McMinn, Ceanothus 236. 1942. 



Erect, rigid'y branched shrub, 1—2 m. high, the young branchlets tomentulose. Leaves oppo- 

 site, elliptic-ovate, 6-15 mm. long, entire or commonly obscurely denticulate, grayish green above 

 and sparsely tomentulose or glabrous, paler beneath and usually tomentulose at least when young ; 

 flowers umbellate, white, on very short axillary peduncles ; capsules 5 mm. broad, the horns 

 dorsal, spreading, scarcely 1 mm. long. 



Drv mountain ridges, especirlly on the desert slopes, Upper Sonoran Zone; Inner Coast Ranges, San Luis 

 Obispo County, and the Tehachapi Mountains, California, to the San Pedro Martir Mountains, Lower California; 

 the eastern slope of the Sierra Nevada, Mono, and Inyo Counties, to the Panamint Mountains, Cajifornia, east 

 to Nevada and northwestern Arizona. Type locality: borders of pine forests near Tehachapi, Kern County, 

 California. April-May. 



30. Ceanothus perplexans Trelease. Cup-leaved Ceanothus. Fig. 3140. 



Ceanothus perplexans Trelease in A. Gray, Syn. Fl. N. Amer. P: 417. 1897. 

 Ceanothus Greygii var. perplexans Jepson, Man. Fl. PI. Calif. 623. 1925. 



Erect stiffly branched shrub, 1-2 m. high, the young branches conspicuously roughened by 

 the persistent stipules, young twigs tomentose. Leaves opposite, oblong-obovate to nearly orbicu- 

 lar, 1-2 cm. long, entire or often conspicuously denticulate all around, soon glabrous above and 

 glossy yellow-green, canescent beneath and more or less densely tomentose ; flowers white, um- 

 bellate ; capsules 5 mm. long with smooth exocarp, the horns entirely absent or, when present, 

 dorsal and very minute. 



Dry mountain ridfres, Upper Sonoran Zone; San Jacinto Mountains, California, south to northern Lower 

 California. Type locality: southwestern California. March-May. 



31. Ceanothus cuneatus (Hook.) Nutt. Common Buck-brush. Fig. 3141. 



Rhamnus cuneatus Hook. Fl. Bor. Amer. 1 : 124. 1829. 



Ceanothus cuneatus Nutt. in Torr. & Gray, Fl. N. Amer. 1:267. 1838. 



Ceanothus oblanceolatus Davidson, Bull S. Calif. Acad. 20:53. 1921. 



Rigid erect shrub, 1-2.5 m. high, with stiff divergent grayish branches, usually tomentulose 

 when young. Leaves opposite, oblong-obovate, cuneate at base, 8-15 mm. long, entire, dull bluish 

 green above and glabrous, finely whitish-tomentose beneath in the areolae; flowers umbellate, 

 white; capsules 5 mm. broad, the horns erect, conspicuous, but rather slender, exocarp smooth 

 between the horns and usually with small apical crests. 



Upper Sonoran and Transition Zones; Willamette Valley, Oregon, south to northern Lower California; 

 a widely distributed and variable species, perhaps comprising several subspecies. Type locality: originally col- 

 lected by Douglas "near the sources of the Multnomak [Willamette] River, in sandy soils, growing under the 

 shade of Pinus Lambertiana." Feb.-April. 



32. Ceanothus Ferrisiae McMinn. Coyote or Ferris' Ceanothus. Fig. 3142. 



Ceanothus Ferrisiae McMinn, Madroiio 2:89. 1933. 



Erect shrub, 1-2 m. high, with stiff divergent or arched branches and numerous lateral stri- 

 gose branchlets. Leaves opposite, orbicular, obtuse or rounded at base, 15-25 mm. long, 1 -veined 

 from the base, regularly or irregularly short-toothed or sometimes nearly or quite entire, dark 

 green and glabrous above, microscopically canescent beneath ; flowers white, in small umbels ; 



