474 MIMOSACEAE 



2. Crataegus columbiana Howell. Columbia Thorn-apple. Fig. 2541. 



Crataegus columbiana Howell, Fl. N.W. Amer. 1: 163. 1898. 



A shrub or small tree 2-5 m. high, usually much branched, the thorns stout, 2-5 cm. long-. 

 Leaves cuneate-obovate, 2-5 cm. long, usually incisely 5-9-lobed, irregularly serrate above the 

 cuneate base, the teeth often gland-tipped, sparingly pubescent above, glabrous below or sparsely 

 hairy in the axils of the principal veins ; branches of the corymb and pedicels glabrous or glabrate ; 

 flowers many ; sepals long-triangular, acuminate, often glandular-serrate, very sparingly villous ; 

 fruit purple or red. 



Along streams, Arid Transition Zone; southeastern British Columbia, eastern Washington and Oregon to 

 northeastern California. Type locality: common along the Columbia River and its tributaries east of the Cascade 

 Mountains. April-May. 



3. Crataegus Piperi Britt. Piper's Thorn-apple. Fig. 2542. 



Crataegus Piperi Britt. Torreyal:55. 1901. 



A much branched shrub, 2-3 m. high, the thorns rather slender, 3-5 cm. long, dark brown. 



Leaves broadly oval, 2-4 cm. long, the teeth sharp, gland-tipped, incised and doubly serrate above 



the middle, merely serrate on the cuneate base, sparingly strigose on both surfaces ; pedicels and 



hypanthium densely villous; sepals long-triangular, 4-5 mm. long, usually glandular-toothed; 



fruit coral-red, spherical or nearly so, about 12 mm. broad, sparingly pubescent. 



Along streams and on moist slopes, Arid Transition and Upper Sonoran Zones; eastern Washington, eastern 

 Oregon, and Idaho. Type locality: Pullman, Washington. April-May. 



6. HETEROMELES M. Roem. Fam. Nat. Syn. 3: 105. 1847. 



An unarmed shrub or small tree, with simple coriaceous evergreen toothed leaves, and 

 minute stipules. Flowers small, white, in terminal corymbose panicles. Hypanthium tur- 

 binate, partly adnate to the ovary. Sepals 5, persistent. Petals 5, rounded, concave, 

 spreading. Stamens 10, in pairs opposite the sepals ; filaments dilated at base and some- 

 what connate. Ovary 2-3-celled ; ovules 2 to each cell, ascending ; styles 2-3. Fruit a red 

 ovoid berry-like pome, the fleshy hypanthium connate with the membranaceous carpels 

 to the middle, and the thickened sepals curved over them above. 



A monotypic California genus, closely related to Photinia of China and Japan. 



1. Heteromeles arbutifolia (Ait.) M. Roem. Tollon, Christmas Berry. 



Fig. 2543. 



Crataegus arbutifolia Ait. Hort. Kew. 3: 202. 1811. Not Lam. 1783. 

 Photinia arbutifolia Lindl. Trans. Linn. Soc. 13: 103. 1821. 

 Heteromeles arbutifolia M. Roem. Fam. Nat. Syn. 3: 105. 1847. 

 Photinia salicifolia Presl, Epimel. Bot. 204. 1849. 



Heteromeles Fremontiana Decn. Nouv. Ann. Mus. Paris 10: 144. 1874. 

 Heteromeles salicifolia Abrams, Bull. N.Y. Bot. Gard. 6: 381. 1910. 



Arborescent shrub or small tree 2-10 m. high, the young branchlets tomentulose. Leaves 

 5-10 cm. long, narrowly oblong to oblong-lanceolate, rather pungently and remotely serrate or 

 dentate, coriaceous, dark green and shining above, pale beneath, glabrous or sparsely tomentulose ; 

 corymbs many- flowered, often 10-15 cm. broad, the branches sparsely tomentulose; hypanthium 

 about 3 mm. high ; sepals short, triangular ; petals suborbicular, 4 mm. long ; fruit broadly ovoid, 

 4-6 mm. in diameter, bright red. 



Hillsides and canyons, at its best in deep rich soils, mainly Upper Sonoran Zone; California from Humboldt 

 and Shasta Counties to Mariposa County, and in the Coast Ranges to northern Lower California. Type locality: 

 Monterey, California. April-July. 



Yellow-berried plants are sometimes found in the southern Coast Ranges, and on San Clemente and Santa 

 Catalina Islands the berries are usually larger. Both of these variants have been given varietal names by some 

 botanists. 



Family 67. MIMOSACEAE. 

 Mimosa Family. 



Herbs, shrubs, or trees, with alternate mostly compound leaves, and small regu- 

 lar mostly perfect flowers, in heads, spikes, or racemes. Calyx 3-6-toothed or -lobed. 

 Corolla of as many distinct or more or less united valvate petals. Stamens as many 

 as the petals, twice as many or numerous, distinct or monadelphous. Pistil solitary ; 

 ovary 1 -celled ; ovules several or numerous ; style simple. Fruit a legume. 



About 40 genera and 1,500 species, mostly of tropical distribution. This, and the three following families, 

 are often united under the name Leguminosae. 



Stamens united below into a tube. 1. Calliandra. 

 Stamens distinct or united only at the base. 



Stamens numerous, at least more than 10; anthers not gland-tipped. 2. Acacia. 



Stamens 10; anthers gland-tipped. 3. Prosopis. 



