26 HOUGH'S AMERICAN WOODS. 



GENUS CEANOTHUS, LINNAEUS. 



Leaves mostly alternate, petioled, coriaceous or somewhat so, glabrous or vari- 

 ously pubescent, deciduous or persistent, with slender stipules falling away early, 

 Flowers perfect, in showy terminal or axillary thyrsoid or cymose clusters, blue 

 or white and with colored pedicels ; calyx colored. 5-lobed, cohering with the 

 ovary below, the triangular lobes incurved and deciduous ; petals much exserted, 

 hooded, spreading, with long slender claws ; stamens 5, opposite the petals and 

 inserted with them, spreading and often persistent, with long filaments and 

 introrse 2-celled anthers longitudinally dehiscent ; pistil with three short styles 

 united below and single 3-celled and usually 3-lobed ovary surrounded with a 

 fleshy persistent disk and containing a single erect orthotropous ovule in each 

 cell. Fruit subglobose, 3-lobed, drupe-like at first, with persistent calyx-tube 

 adnate at base, finally becoming dry and separating into three 2-valved dehiscent 

 cocci each liberating a single obovate-lenticular seed with thin crustaceous testa, 

 ventral raplie and fleshy albumen. 



The genus is composed of about thirty species, mainly of shrubs, and is confined 

 to North America, the greater number being found in California where some 

 natural hybrids seem to occur. The name is of classical Greek origin and of 

 rather obscure application. 



177. CEANOTHUS ARBOREUS, GREENE.* 

 TREE MYRTLE. 



Ger., Baumische My He / Fr., Myrte d'arbre j Sp., MirtodeArbol. 



SPECIFIC CHARACTERS : Leaves alternate, ovate to broad elliptical, 2-4 in. long, 

 acute, rounded at base, glandular-crenate-serrate, dark green above, and with 

 pale dense short tomentum and prominent veins beneath ; petioles A-f in. in length 

 and, as with the new growths, densely pale-tomentose: stipules about i in. long and 

 earl} 7 deciduous ; branchlets slightly angled. Flowers pale blue, produced in 

 ample compound hoary-pubescent thyrsoidal clusters on axillary peduncles near 

 the extremities of youno branches, with slender hair-like pedicels produced in the 

 axils of large scarious hoary caducous bracts. Fruit black when mature and 

 in. in diameter. 



(Arboreus is a Latin adjective from arbor, tree.) 



Tliis is a small handsome tree with wide top, rarely over 25 ft. 

 (7.50 in.) in height, or with trunk more than 10 or 12 in. (0.30 m.) 

 in diameter. The bark, at first of a gray color and quite smooth, 

 becomes with age of a dark brown color fissured into small square 

 thickish scales. It 'is the most truly arboreal representative of the 

 genas, though in many regions is only a bush with many slender 

 branches. 



HABITAT. The islands of Santa Catalina, Santa Cruz and Santa 

 Rosa, off the coast of southern California, growing along the slopes 

 and sides of canons. 



PHYSICAL PROPERTIES. Wood very heavy, hard, close-grained, 

 with annual layers marked by an aggregation of fine open ducts, and 

 of a red-brown color with lighter sap-wood. Specific Gravity, 0.7781 ; 

 Percentage of Axli, 2.05; Relative Approximate Fuel Value, 0.7622; 

 Weight of a Cubic Foot in Pounds, 48.49. 



* Ceanothus velutinus, var. arboreus, Sarg. 



