RHAMNACER, SILVA OF NORTH AMERICA. 41 
CEANOTHUS. 
FLowers perfect ; calyx 5-lobed, the lobes valvate in estivation; inflexed; petals 
9, inserted under the margin of the disk, unguiculate, wide-spreading; ovary im- 
mersed in and more or less adnate to the disk. Fruit drupaceous, 3-coccous. 
Ceanothus, Linneus, Act. Ups. i. 17; Gen. ed. 4, 414. — Gray, Gen. Jil. ii. 181.— Bentham & Hooker, Gen. i. 
A. L. de Jussieu, Gen. 380. — Brongniart, Mém. Rham- 378. — Baillon, Hist. Pl. vi. 80. 
nées, 62. — Endlicher, Gen. 1098. — Meisner, Gen. 70.— Paliurus, Adanson, Fam. Pl. ii. 304 (in part). 
Forrestia, Rafinesque, NV. Y. Med. Rep. hex. 2, iii. 422, v. 351. 
Small trees or shrubs, sometimes prostrate, with flexible, often angled, unarmed, or rigid terete 
spinescent branches. Leaves alternate or rarely opposite, petioled, coriaceous or subcoriaceous, entire, 
serrate, spinulose-dentate, or glandular-ciliate, glabrous, canescent-pubescent, or densely tomentose on 
the lower surface, triple-veined from the base or pinnately veined, deciduous or persistent; stipules 
slender, membranaceous and caducous, or thick and corky at the base with deciduous tips. Flowers 
produced in umbel-like fascicles aggregated in dense or prolonged terminal or axillary thyrsoid cymes 
or panicles, blue or white, often fragrant. Pedicels colored. Calyx colored, with a turbinate or hemi- 
spherical tube and triangular membranaceous petaloid lobes, deciduous by a circumscissile line. Disk 
fleshy, thickened above, filling the tube of the calyx. Petals alternate with and much longer than 
the calyx-lobes, exserted, spreading or reflexed, deciduous, the long limb enfolded round the stamens in 
estivation. Stamens five, inserted with and opposite to the petals, often persistent ; filaments filiform, 
spreading ; anthers didymous or four-lobed, introrse, two-celled, the cells opening longitudinally. Ovary 
three-celled, sometimes three-angled, the angles often surmounted by a fleshy gland persistent in the 
fruit ; styles short, united below; stigmas introrse or terminal; ovules solitary, erect from the base of 
the cell, anatropous, the raphe next the axis, the micropyle inferior. Fruit subglobose, three-lobed, 
supported on the base of the persistent and commonly adnate calyx; epicarp thin and soon becoming 
dry, dehiscent into three crustaceous or cartilaginous longitudinally two-valved cocci. Seed erect, 
obovate-lenticular, with a broad basal excrescence surrounding the hilum; testa thin, crustaceous ; 
raphe ventral ; albumen fleshy. Embryo axile; cotyledons oval or obovate; radicle very short, next 
the hilum.’ 
The genus Ceanothus is confined to the temperate and warmer regions of North America. About 
thirty species are distinguished,’ the largest number belonging to California. Here Ceanothus is one of 
the prominent and striking features of the mountain and foothill vegetation, especially on the ranges of 
the coast region south of the Bay of San Francisco, where many species with showy flowers are aggre- 
gated, and in the arid southern deserts, where species with interlocking branches terminating in long 
rigid spines form impenetrable thickets often of great extent.° Two species are widely distributed 
in the eastern part of the continent* from Manitoba to Texas, and from the ocean to the base of the 
Rocky Mountains ; and two others occur in the maritime region of the southern Atlantic states.” The 
1 Dr. Parry first recorded (Proc. Davenport Acad. v. 164) the x. 333.— Trelease, Proc. Cal. Acad. ser. 2, i. 106. — Parry, Proc. 
fact that the nutlets of many species when relieved from the disk Davenport Acad. v. 162. 
expel the smooth-coated seed through the ventral slit with consid- 8 A number of forms of Ceanothus now believed to be hybrids 
erable force. To this provision, which serves to protect the ripe have been noticed in California (Trelease, Garden and Forest, i. 7 ; 
seed from omnivorous animals and insures its reaching the surface Proc. Cal. Acad. ser. 2, i. 116. — Parry, Proc. Davenport Acad. v. 
of the ground, he ascribes the gregarious habit peculiarly charac- 170). 
teristic of many of the Californian species. 4 Watson & Coulter, Gray’s Man. ed. 6, 112. 
2 Torrey & Gray, Fl. N. Am. i. 264.— Watson, Proc. Am. Acad. 5 Chapman, Fi. 74. 
