ERICACEAE 



731 



divergent branchlets reddish brown and more or less pubescent or light purple, pilose, 

 and covered with a glaucous bloom when they first appear, becoming bright red at the 

 end of their first season, with bark separating freely into thin more or less persistent 

 scales. Bark of young stems and of the branches thin, smooth, dark red, exfoliating 

 in large thin scales, becoming on old trunks '-^' thick, irregularly broken by 

 longitudinal furrows and divided into square appressed plate-like light gray or 



nearly white scales faintly tinged with red on the surface. Wood heavy, close- 

 grained, soft and brittle, light brown tinged with red, with lighter colored sapwood 

 of 30-40 layers of annual growth. 



Distribution. Dry gravelly benches at elevations of 6000-8000 above the sea 

 oil the Santa Catalina and Santa Rita Mountains, southern Arizona, and southward 

 ulong the Sierra Nevada of Chihuahua. 



7. VACCINIUM, L. 



Shrubs or rarely small trees, with slender branchlets, and fibrous roots. Leaves 

 membranaceous or coriaceous, deciduous or persistent. Flowers small, on bibrac- 

 teolate pedicels, in many-branched axillary racemes, or solitary, their bracts small 

 or foliaceous; calyx-tube adnate to the ovary, 4-5-lobed, the lobes valvate in the 

 bud, persistent; corolla epigynous, 4 or 5-toothed, the teeth imbricated in the bud, 

 urceolate-campanulate; stamens 8-10, inserted on the base of the corolla under the 

 thick obscurely lobed epigynous disk; filaments filiform, free, usually hirsute; anthers 

 awned on the back, the cells produced upward into erect spreading tubes dehiscent 

 by terminal pores; ovary inferior, 4 or 5-celled,. the cells sometimes imperfectly 

 divided by the development from the back of a false partition; style filiform, erect; 

 stigma minute; ovules attached to the interior angle of the cell by a 2-lipped pla- 

 centa, anatropous. Fruit a berry crowned with the calyx-limb, 4 or o or imperfectly 

 8 or 10-celled, the cells many-seeded. Seed minute, compressed, ovoid or reniform ; 

 seed-coat crustaceous; embryo clavate, minute, surrounded by fleshy albumen, axile, 

 erect; cotyledons ovate; radicle terete, turned toward the hilum. 



Vaecinium with about one hundred species is distributed through the boreal and 

 temperate regions of the northern hemisphere, and occurs within the tropics at high 

 elevations above the sea north and south of the equator. Of the twenty-five or thirty 



