RHAMNACER, SILVA OF NORTH AMERICA. 43 
CEANOTHUS THYRSIFLORUS. 
Blue Myrtle. California Lilac. 
BRANCHLETS conspicuously angled. Inflorescence compound on leafy branches. 
Leaves alternate, prominently 3-ribbed, minutely glandular-serrate. 
Ceanothus thyrsiflorus, Eschscholtz, Wem. Acad. Sci. St. Rep. iv. 74; Bot. Mex. Bound. Surv. 45; Bot. Wilkes 
Pétersbourg, x. 285. — Hooker, Fl. Bor.-Am. i. 125.— Explor. Exped. 263. — Newberry, Pacific Rh. Rh. Rep. vi. 
Don, Gen. Syst. ii. 37. — Hooker & Arnott, Bot. Voy. 69. — Cooper, Pacific R. R. Rep. xii. 57. — Koch, Dendr. 
Beechey, 136, 328. —Torrey & Gray, Fl. N. Am. i. 266. — i. 621. — Watson, Proc. Am. Acad. x. 334. — Brewer & 
Dietrich, Syn. i. 813.— Loudon, Arb. Brit. ii. 540. — Watson, Bot. Cal. i. 102. —Sargent, Forest Trees N. Am. 
Lindley, Bot. Reg. xxx. t. 38. — Nuttall, Sylva, ii. 44, t. 10th Census U. S. ix. 41.— Parry, Proc. Davenport 
57. — Bentham, Bot. Voy. Sulphur, 10; Pl. Hartweg. Acad. v. 170. — Trelease, Proc. Cal. Acad. ser. 2, 108. 
302. — Ann. Gand. iii. 11, t. 107. — Torrey, Pacific R. R. 
A small tree, rising sometimes to the height of thirty-five feet, with a trunk twelve or fourteen inches 
in diameter, dividing, five or six feet from the ground, into many wide-spreading slender branches ; 
or more often a tall or low shrub. The bark of the trunk is thin with a bright red-brown surface 
separating into thin narrow appressed scales. The branchlets are conspicuously angled, pale yellow- 
green, and slightly pubescent when they first appear, but soon become glabrous. The leaves are 
persistent, oblong or oblong-ovate, smooth and lustrous on the upper surface, and paler and slightly 
pubescent beneath, especially along the principal veins; they are an inch or an inch and a half long 
and half an inch to an inch broad, with prominent orange-colored veins, and are borne on stout peti- 
oles from a third to half an inch in length. The stipules are membranaceous, acute, and early decid- 
uous. The fragrant blue or white flowers appear in early spring, and are arranged in small pedunculate 
corymbs produced from the axils of minute deciduous bracts and collected into slender rather loose 
thyrsoid clusters two or three inches long, terminating long leafy pedunculate branchlets of the year ; 
these spring from the axils of upper leaves or of small scarious bracts, and are usually surmounted by 
the terminal leafy shoot of the branch. The fruit, which ripens from July to September, is black at 
maturity and is not crested. The seed is a line long, with a smooth dark brown or black coat. 
Ceanothus thyrsiflorus belongs to the mountainous region of western California, where it is widely 
distributed through the coast ranges from Mendocino County in the north to the valley of the San Luis 
Rey River. It is usually found on shady hillsides growing on the borders of the forest, often in the 
neighborhood of streams. It attains its greatest size’ on the hills overlooking the swamps of the Noyo 
River in Mendocino County, where it is associated with the Redwood, the Douglas Fir, the Buckthorn, 
and various Willows and Oaks ; and in the Redwood forests of the Santa Cruz Mountains. Towards 
the southern limit of its range it is reduced to a low shrub,” often flowering and ripening its fruit on 
the wind-swept shores of the ocean when only a foot or two high. 
The wood of Ceanothus thyrsiflorus is close-grained and rather soft, with obscure medullary rays. 
It is ight brown, with thin darker colored sapwood, and when absolutely dry has a specific gravity of 
0.5750, a cubic foot weighing 35.83 pounds. 
Ceanothus thyrsiflorus was discovered in 1816 by Eschscholtz, and was introduced into English 
1 As noticed by T. S. Brandegee. thus in the field, reached the conclusion (Proc. Davenport Acad. 
2 Ceanothus thyrsiflorus shows a tendency to cross with other v. 170) that C. Lobbianus (Hooker, Bot. Mag. t. 4810) and C. 
species and produce natural hybrids. Several of these have been  Veitchianus (Hooker, Bot. Mag. t. 5127) are hybrids of this spe- 
noticed ; and Dr. Parry, who long studied the Californian Ceano- cies. 
