BUCKTHORN FAMILY 67 



Type locality: "Subalpine hills near the source of the Columbia and at the Kettle Falls." April-July. Mountain 

 Balm. 



Ceanothus velutinus var. laevigatus (Hook.) Torr. & Gray, Fl. N. Amer. 1: 686. 1838 Di'^tinguished 

 from the typical species by the glabrous twigs and leaves. Vancouver Island southward west of the Cascade 

 Mountains to the North Coast Ranges, California. Type locality: Nootka, Vancouver Island, British Columbia. 



Ceanothus velutinus var. Lorenzenii Jepson, Man. Fl. PI. Calif. 619. 1925. Leaves smaller, not varnished 

 above; panicles shorter. Probably a hybrid between C. velutinus and C. cordulatus. Occasional from Mount 

 Shasta to the southern Sierra Nevada, California. Type locality: Junction Meadow, Tulare County. 



3. Ceanothus arboreus Greene. Catalina Ceanothus. Fig. 3113. 



Ceanothus arboreus Greene, Bull. Calif. Acad. 2: 144. 1886. 



Ceanothus velutinus var. arboreus Sargent, Garden & Forest 2: 364. 1889. 



Ceanothus arboreus var. glabra Jepson, Man. Fl. PI. Calif. 619. 1925. 



Arborescent shrub or small tree. 3-6 m. high, twigs remaining canescent with a fine dense 

 tomentum for one or two years then becoming glabrous and reddish brown. Leaves 3-8 cm. long, 

 broadly ovate to elliptic, obtuse or acute, obtuse to subcordate at base, glandular-serrulate, dull 

 green above and velvety with a fine soft puberulence, canescent beneath with a dense short to- 

 mentum, prominently 3-ribbed ; panicles ample, often 8-12 cm. long; flowers pale blue; capsule 

 6-7 mm. broad, 3-lobed, wrinkled and prominently crested on the back of each lobe. 



Mountain slopes. Upper Sonoran Zone; Santa Cruz, Santa Rosa, and Santa Catalina Islands, California. 

 Type locality: northern slopes at higher elevations, Santa Cruz Island. March-April. 



4. Ceanothus tomentosus Parry. Woolly-leaved Ceanothus. Fig. 3114. 



Ceanothus tomentosus Parry, Proc. Davenp. Acad. 5: 190. 1889. 



Ceanothus otiganthus var. tomentosus K. Brandg. Proc. Calif. Acad. II. 4: 198. 1894. 



Shrub, 1-3 m. high with grayish brown bark, the branchlets slender, rusty-tomentose when 

 young. Leaves 8-25 mm. long, ovate to elliptic, glandular-serrulate, dull green and minutely 

 velvety above, densely white-tomentose beneath ; peduncles often bearing one or two leaves at 

 base; panicle simple, 2.5-5 cm. long; flowers pale violet-blue or sometimes nearly white; cap- 

 sule about 4 mm. broad, 3-lobed, the lobes smooth or slightly crested. 



Dry rocky ridges. Upper Sonoran Zone; foothills of the Sierra Nevada, from Nevada County to Mariposa 

 County, California. Type locality: brown sandstone ledges, lone, Amador County. April-May. 



Ceanothus tomentosus var. olivaceus Jepson, Man. Fl. PI. Calif. 621. 1925. Under surface of the leaves 

 gray-green with a fine velvety pubescence; capsule more glutinous and becoming very dark in age. Chaparral 

 slopes of southern California in San Bernardino and San Diego Counties south to northern Lower California. 

 Type locality: Clevinger Canyon, Ramona, San Diego County. 



5. Ceanothus cyaneus Eastw, San Diego Ceanothus. Fig. 3115. 



Ceanothus cyaneus Eastw. Proc. Calif. Acad. IV. 16: 361. 1927. 



Arborescent shrub up to 4 m. high, with gray-brown bark, the branchlets sparsely puberulent 



or glabrous, usually bearing scattered brownish sessile glands. Leaves elliptic-ovate to ovate, 



finely glandular-serrulate, 1.5-4 cm. long, light green and glabrous above, scarcely paler beneath, 



thinly puberulent ; peduncles elongated, the lower often bearing a few leaves ; panicles simple 



or the terminal ones compound, 5-15 cm. long; flowers bright blue; capsule shallowly 3-lobed, 



smooth, crests small, usually evanescent. 



Canyon slopes, Upper Sonoran Zone; foothills of eastern San Diego County, California. Type locality: 

 Lakeside, San Diego County, California. April-May. 



6. Ceanothus oliganthus Nutt. Hairy Ceanothus. Fig. 3116. 



Ceanothus oliganthus Nutt. in Torr. & Gray, Fl. N. Amer. 1:266. 1838. 

 Ceanothus hirsutus Nutt. in Torr. & Gray, loc. cit. 

 Ceanothus divaricatus Nutt. in Torr. & Gray, loc. cit. 



Arborescent shrub, 1.5-3 m. high, the branches not rigid-spinescent, hirsute, the older be- 

 coming smooth and brownish. Leaves 1 .5-4.5 cm. long, ovate, obtuse to acutish, rounded to sub- 

 cordate at base, glandular-denticulate, dull green above and sparingly pubescent, pale beneath and 

 more or less densely hirsute-pubescent, the veins slender ; petioles 1 cm. long or less ; panicles 

 simple, 1 . 5-3 cm. long ; peduncles short, leafless ; flowers deep violet ; capsule about 4 mm. 

 broad, shallowly lobed, the lobes resinous and wrinkled, rather strongly crested. 



Chaparral slopes, Upper Sonoran Zone; cismontane region of southern California from southern San Luis 

 Obispo County to San Diego County. Type locality: Santa Barbara. March-April. 



Ceanothus oliganthus var. Orcuttii (Parry) Jepson, Man. Fl. PI. Calif. 621. 1925. {Ceanothus Orcuttii 

 Parry, Proc. Davenp. Acad. 5 : 194. 1889.) Flowers pale violet; capsule villous, more viscid and wrinkled. 

 Cuyamaca Mountains, San Diego County, California. Type locality: high mountains east of San Diego. 



7. Ceanothus thyrsiflorus Esch. Blue-brush or Blue-blossom. Fig. 3117. 



Ceanothus thyrsiflorus Esch. Mem. Acad. St. Petersb. VI. 10: 285. 1826. 



Arborescent shrub or small tree, 1-4 m. high with slender flexible ascending branches, the 

 younger twigs angled, green, glabrous or sparsely pubescent, somewhat viscid. Leaves 2-6 cm. 

 long, oblong-elliptic, acutish or obtuse at apex, narrowed at base, rather remotely and sometimes 

 obscurely glandular-serrulate ; dark green and glabrous above, pale green below and sparsely 

 hairy on the prominent veins ; panicle simple or often compound, 4-8 cm. long ; peduncles often 



