92 NORTH AMERICAN FLORA [Vorume 29 
39. XYLOCOCCUS Nutt. Trans: Am. Phil. Soc. II. 8: 358. 1843. 
Shrubs with erect densely branched stems. Leaves alternate, persistent; blades broad, 
entire, revolute, short-petioled. Flowers few in terminal unbranched panicles with stout 
rachis and pedicels, the bracts scale-like. Calyx persistent; lobes 5, or rarely 4, very broad, 
much longer than the tube, reflexed at maturity. Corolla oblong-urceolate; lobes 5, or rarely 4, 
very small, spreading or recurved. Stamens 10, or rarely 8, included; filaments elongate, 
dilated near the base, unappendaged, pubescent; anthers broad, oval or ovoid, each sac with a 
slender awn. Ovary ovoid, 5-celled or tarely 4-celled, seated in a disk, pubescent; style 
elongate; stigma minute. Drupe dry, with a smooth pericarp and a thin pulp, the woody 
nutlets united into a solid stone. 
Type species, Xylococcus bicolor Nutt. 
1. Xylococcus bicolor Nutt. Trans. Am. Phil. Soc. II. 8: 259. 1843. 
Comarostaphylis bicolor Klotzsch, Linnaea 24: 78. 1851. 
Arctostaphylos Veatchii Kellogg, Proc. Calif. Acad. 2: 19. 1863. 
Arctostaphylos bicolor A. Gray, Proc. Am. Acad. 7: 366. 1868. 
Arctostaphylos Clevelandi A. Gray, Syn. Fl. N. Am. 2!: 29, 1878. 
A shrub densely branched above, with cinereous-tomentulose twigs; leaf-blades ovate or 
oval, often apparently narrowly so on account of the revolute margins, obtuse or acutish, 2-6 
cm. long, entire, ultimately veiny and glabrous or nearly so above, more or less tomentose 
beneath, narrowed or rounded at the base, short-petioled; panicles short, recurved, densely 
few-flowered, the rachis and pedicels toméntulose; calyx about 5 mm. wide, the lobes reniform 
or ovate-reniform, obtuse, tomentulose; corolla 8-9 mm. long, white or pink, sometimes rose- 
colored, the lobes minute; stamens 5-6 mm. long, the filaments very slender above the dilated 
base, villous, the anthers nearly 2 mm. long; drupes globular, 6-8 mm. in diameter, often 
purplish-red. : . 
TYPE LOcALITy: Monterey, California; but probably San Diego, as the plant is not found in 
the Monterey region. 
DistTRiBuTION: Southern California and northern Lower California. 
40. UVA-URSI* (Tourn.) Mill. Gard. Dict. Abr. ed. 4. 1754. 
Arctostaphylos Adans, Fam. Pl. 2: 165. 1763. 
Moairania Neck, Elem. 1: 219. 1790. 
Xerobotrys Nutt. Trans. Am. Phil. Soc. II. 8: 267. 1843. 
Daphnidostaphylis Klotzsch, Linnaea 24: 79. 1851. 
Low spreading or erect shrubs or small trees, with exfoliating bark, on trunks and old 
branches often polished and reddish-brown. Leaves alternate, petioled or sessile, firm or 
coriaceous, evergreen, often similar on both surfaces and vertical by a twist of the petiole. 
Flowers in terminal racemes or panicles, small, nodding on slender pedicels bracteolate at 
base, and borne in the axils of persistent or deciduous bracts. Calyx 5-parted, the oblong to 
orbicular lobes persistent. Corolla urceolate to oblong-campanulate, 5-lobed, the lobes short, 
rounded, recurved, imbricate in the bud. Stamens 10, included; filaments dilated and usually 
hairy at base; anthers erect, short, introrse, with 2 recurved dorsal awns; pollen-sacs opening 
by a terminal pore. Disk 10-lobed. Ovary 4-10-celled; ovules solitary in the cavities; style 
slender. Drupe with 4-10 seed-like nutlets, irregularly separable or united into a solid stone; 
pericarp thin or often with a granular pulp. 
Type species, Arbutus Uva-ursi L. 
Pericarp with a granular pulp; nutlets separate, irregularly coalescent or 
rarely united into a solid stone. 
Leaf-blades rounded at apex, not mucronate; fruit bright-red and insipid. 1. U. Uva-ursi. 
Leaf-blades acute to rounded and mucronate or mucronulate at apex; 
fruit reddish-brown to yellowish-brown, acid. 
Fruit depressed-globose, globose, or rarely ovoid, with copious granular 
ulp. 
Pedicels and ovaries glabrous; leaves dull- or bright-green; branch- 
lets never setose-hispid. 
Low alpine shrubs with prostrate or decumbent branches; 
leaf-blades less than 15 mm. broad. 
*By LeRoy ABRAMS. 
