78 RHAMNACEAE 



glabrous and usually reddish brown the second year. Leaves opposite, elliptic to broadly obovate, 

 2-5 cm. long, narrowly revolute, prominently and sharply toothed all around, glossy green above 

 and glabrous or with a few hairs on the midrib, glabrous below or sparsely pubescent on the 

 veins, umbels many-flowered, on short stout peduncles; flowers violet-blue; capsules 3.5-4 mm. 

 broad and scarcely as high, the horns small, scarcely 1 mm. high. 



Usually in sandy soils, Humid Transition Zone; near the coast, Mendocino County to Marin County, Cali- 

 fornia. Type locality: Anchor Bay, Mendocino County, California. April. 



Ceanothus gloriosus var. exaltatus J. T. Howell, Leaflets West. Bot. 2: 44. 1937. Erect shrub, 1-2 m. 

 high, rigidly much-branched, the ultimate branches divaricate; otherwise like the typical species. Ridges and 

 canyons, Humid Transition Zone; Outer Coast Ranges, Mendocino, Sonoma, and Marin Counties, California. 

 Type locality: Vine Hill district near Sebastopol, Sonoma County. 



38. Ceanothus Masonii McMinn. Bolinas Ceanothus. Fig. 3148. 



Ceanothus Masonii McMinn, Madroiio 6: 171. 1942. 



Erect or erect-spreading shrub, 0.6-2 m. high, with stout rather stiff divaricate branches, the 

 young branchlets brown or purplish, tomentulose, becoming glabrous in age. Leaves opposite, 

 broadly elliptic to nearly orbicular, 6-18 mm. long, obtuse to rounded or truncate at apex, rounded 

 or occasionally cuneate at base, denticulate all around with a number of small triangular minutely 

 mucronulate teeth, dark green and shining above, microscopically canescent between the netted 

 veinlets beneath ; stipules prominent, persistent ; flowers dark blue or violet, in small umbel-like 

 clusters terminating short pedunculate lateral branchlets; fruiting capsule globose, about 3.5 mm. 

 broad, with 3 short apical or subapical horns and without intermediate crests. 



Dry ridges, Humid Transition Zone; known only from Bolinas Ridge, Marin County, California. Type 

 locality: "Along trail on east end of Bolinas Ridge." March-April. 



39. Ceanothus sonomensis J. T. Howell. Sonoma Ceanothus. Fig. 3149. 



Ceanothus sonomensis J. T. Howell, Leaflets West Bot. 2: 162. 1939. 



Erect shrub with nearly straight rather stiff gray or brown stems, 5-15 dm. high, bearing 

 opposite short almost spur-like lateral branchlets. Leaves opposite, cuneate-obovate to nearly 

 orbicular, 5-15 mm. long, 3-toothed at the apex and often with 1-2 pairs of lateral teeth, thick, 

 firm and somewhat holly-like, the margins revolute, glossy above, microscopically tomentulose 

 beneath, subsessile; flowers blue to lavender, in small nearly sessile umbels; fruiting capsules 

 globose, 3-4 mm. broad, with 3 short subdorsal horns and low ridge-like intermediate crests. 



Mountain slopes, Upper Sonoran Zone; Hood Mountain Range, Sonoma County, California, the type 

 locality. 



40. Ceanothus purpureus Jepson. Napa Ceanothus, Fig. 3150. 



Ceanothus purpureus Jepson, Fl. W. Mid. Calif. 258. 1901. 



Ceanothus Jepsonii var. purpureus Jepson, Man. Fl. PI. Calif. 624. 1925. 



Erect shrub, 1-2 m. high, the branches rigid, divergent, reddish brown and nearly or quite 

 glabrous, clothed with very prominent corky stipules. Leaves opposite, suborbicular to broadly 

 elliptic, strongly undulate, and conspicuously spinose-toothed all around, glossy green and gla- 

 brous above, slightly paler beneath and only inconspicuously tomentulose in the areolae ; flowers 

 umbellate, dark violet-blue ; capsules about 5 mm. broad, horns slender, erect, exocarp smooth 

 between except for 3 small apical crests. 



Mountain ridges. Upper Sonoran and Transition Zones; Napa Range, Napa County, California. Type 

 locality: Wooden Valley Grade, Napa Range, California. Feb.-April. 



41. Ceanothus divergens Parry. Calistoga Ceanothus. Fig. 3151. 



Ceanothus divergens Parry, Proc. Davenp. Acad. 5: 173. 1889. 



Ceanothus prostratus var. divergens K. Brandg. Proc. Calif. Acad. II. 4:210. 1894. 



Shrub, 5-15 dm. high, the main branches rather weak and divergent or arching, but never 

 decumbent or prostrate. Leaves obovate to oblong, with 5-8 coarse spinescent teeth, undulate, 

 dark green, glabrous and shining above, grayish-tomentulose beneath; flowers blue, in small 

 corymbs racemosely disposed on the branchlets ; fruiting capsule nearly globose, about 6 mm. in 

 diameter, with 3 prominent dorsal horns, without prominent intervening crests. 



In rather open chaparral, Upper Sonoran Zone; originally collected by Parry in the vicinity of Calistoga, 

 Napa Valley, Sonoma County, California. Plants at the original station may have been destroyed by cultivation, 

 but plants matching well the type collections are growing at several stations within four to five miles of Calis- 

 toga. Feb. -March. 



Ceanothus divergens subsp. confusus (J. T. Howell) Abraras. {Ceanothus confusus J. T. Howell, Leaflets 

 West Bot. 2: 160. 1939.) Stems decumbent, the main branches with their ends turned upward and 2-4 dm. 

 high. Leaves 6-20 mm. long, ovate to elliptic, more or less cuneate at base, denticulate to spinulose with 3-11 

 teeth. This subspecies is more widespread than the typical species, occurring at middle elevations in the moun- 

 tains of Lake, Sonoma, and Napa Counties. Type locality: Rincon Ridge, Sonoma County, California. 



Ceanothus divergens subsp. occidentalis (McMinn) Abrams. (Ceanothus prostratus var. occidentalis 

 McMinn, Ceanothus 262. 1942.) Plants prostrate forming mats and thereby simulating C. prostratus Benth. 

 of the Sierra Nevada, but the leaves and especially the fruits are essentially the same as those of C. divergens. 

 Leaves usually undulate and slightly troughed above, with 3-6 or rarely more spinulose teeth; capsules 4-S mm. 

 broad, their horns slender and spreading. Near the summits of the higher peaks in the North Coast Ranges of 

 Mendocino, Lake, Sonoma, and Napa Counties, California. Type locality: Cobb Mountain, Lake County, Cali- 

 fornia. 



