RHAMNACE.E 727 



Leaves elliptic, acute at base, glabrous except on the veins below. 



2. C. thyrsiflorus (G). 



Branchlets spinose; leaves with a single midrib, mostly elliptic, rounded or subcordate at 

 base, glabrous. 3. C. spinosus (G). 



1. Ceanothus arboreus Greene. 



Leaves broad-ovate or elliptic, acute, conspicuously glandular-crenate, dark green and 

 softly puberulent on the upper surface, pale and densely tomentose on the lower surface, 

 2^'-4' long and \'-^,\' wide, with prominent veins; petioles stout, pubescent, \'-\' in length; 

 stipules subulate from a broad triangular base, j' long. Flowers pale blue opening in July 

 and August, on slender hairy pedicels 5'-!' long, from the axils of large scarious caducous 

 bracts, in ample compound densely hoary-pubescent thyrsoid clusters 3'-4' long and 

 l|'-2' wide, on a leafy or naked axillary peduncle at the end of young branches. Fruit 

 black, j' across. 



A round-headed tree, 20-25 high, with a straight trunk 6'-10' in diameter, dividing 

 4-5 Q from the ground into many stout spreading branches, and slender slightly angled 

 pale brown branchlets covered with short dense tomentum, becoming in their second season 



Fig. 653 



terete, nearly glabrous, roughened with scattered lenticels and marked by large elevated 

 leaf-scars; often a shrub. Bark of the trunk dark brown, about ' thick, and broken into 

 small square plates separating into thick scales. 



Distribution. Santa Catalina, Santa Cruz, and Santa Rosa Islands of the Santa Barbara 

 group off the coast of southern California; most abundant and of its largest size on the 

 northern slopes of Santa Cruz;on the other islands usually shrubby, with numerous slender 

 stems. 



2. Ceanothus thyrsiflorus Eschs. Blue Myrtle. California Like. 



Leaves oblong or oblong-ovate, minutely glandular-serrate, smooth and lustrous on the 

 upper surface and paler and slightly pubescent on the lower surface, especially along the 3 

 prominent ribs, \'-\\' long and |'-1'wide; petioles stout, \'-\' in length; stipules mem- 

 branaceous, acute. Flowers blue or white, appearing in early spring in small pedunculate 

 corymbs from the axils of minute deciduous bracts, and collected into slender rather loose 

 thyrsoid clusters 2'-3' long in the axils of upper leaves or of small scarious bracts, and 

 usually surmounted by the terminal leafy shoot of the branch. Fruit ripening from July 

 to December, black; seeds T V long, smooth, dark brown or nearly black. 



A tree, occasionally 35 high, with a trunk 12'-14' in diameter, dividing 5-6 from the 



