534 BORAGINACEAE 



2. Coldenia plicata (Torr.) Coville. Plicate Coldenia. Fig. 4163. 



Tiquilia brevifolia var. plicata Torr. Bot. Mex. Bound. 136. 1859. 

 Coldenia Palmeri of S. Wats, and recent authors, not A. Gray. 

 Coldenia plicata Coville, Contr. U.S. Nat. Herb. 4: 163. 1893. 



Stems several from a woody base, finely and usually openly branched dichotomously, form- 

 ing a mat or rounded tuft up to 5 dm. broad; branchlets somewhat 4-angled, rather thinly short- 

 tomentose. Leaves broadly to narrowly obovate or sometimes ovate, narrowed to a petiole of 

 about equal length, 5-10 mm. long, conspicuously plicate by 4-7 pairs of lateral ribs, densely 

 white-silky pubescent on both sides, with a few scattering short-hispid hairs intermingling 

 especially toward the entire narrowly revolute margin ; flowers clustered in the forks and at 

 the ends of the branches ; calyx-lobes subulate, densely villous-tomentose, especially on the 

 inside, 2-2.5 mm. long; corolla blue or lavender, 4 mm. long, the limb about 2.5 mm. broad; 

 style-branches exserted beyond the calyx-lobes ; nutlets about 1 mm. long, ovoid or globular, 

 smooth and shining, usually one or more aborted. 



Usually in sandv soils, Lower Sonoran Zone; in the Mojave Desert along the Colorado River below 

 Needles, and in the Colorado Desert from San Gorgonio Pass east to Arizona and south to Lower California. 

 Type locality: "desert west of the Colorado, California." April-Aug. 



3. Coldenia Palmeri A. Gray. Palmer's Coldenia. Fig. 4164. 



Coldenia Palmeri A. Gray, Proc. Amer. Acad. 8: 292. 1870. 

 Coldenia brevicalyx S. Wats. Proc. Amer. Acad. 24: 62. 1889. 



Stems several from the crown of deep-seated woody roots, woody at base, fimbriate or 

 spreading forming a mat or rounded tuft, 2-4 dm. high, branchlets dichotomous, thinly hirsu- 

 tulous-tomentose, the whitish bark exfoliating in age. Leaves ovate, obovate or rhornbic, 4-10 

 mm. long on petioles as long or longer, the margins sinuate-revolute, irregularly veined with 

 2-3 pairs of lateral veins impressed on the back but not plicate, appressed-pubescent and with a 

 few scattering hispid hairs especially near the margin; calyx 2-3.5 mm. long, glabrescent or 

 short-pubescent within ; corolla 5-7 mm. long ; nutlets nearly globose, about 1 mm. in diameter. 



Sandy soil. Lower Sonoran Zone; western side of the Colorado Desert, California, east to southwestern 

 Nevada and western Colorado, south to Lower California. Type locality: lower Colorado River. April-June. 



4. Coldenia Nuttallii Hook. Nuttall's Coldenia. Fig. 4165. 



Coldenia Nuttallii Hook. Kew Journ. Bot. 3 : 296. 1851. 

 Tiquilia Parviflora Nutt. ex Hook. loc. cit. as a synonym. 

 Tiquilia brevifolia Nutt. ex Torr. Bot. Mex. Bound. 136. 1859. 



Prostrate annual, with slender dichotomously branching stems forming a mat 1-3 dm. 

 broad, rather thinly appressed-pubescent. Leaves ovate to suborbicular, 4-8 mm. long, narrowly 

 revolute and often hispid on the margin, with 2-3 pairs of rather distinct veins impressed on 

 the back, thinly strigose on the upper surface with rather stiff hairs, the hairs a little longer and 

 more spreading on the lower surface ; petioles slender, usually as long or longer than the leaves ; 

 flowers in compact clusters in the forks and at the ends of the branches; calyx-lobes linear- 

 subulate, 4-5 mm. long, villous on the back and sparsely but conspicuously hispid on the margins ; 

 corolla pink or nearly white, little exceeding the calyx, the limb 2-2.5 mm. broad, the tube 

 with 5 triangular scales near the base ; nutlets oblong-ovoid, smooth and shining. 



Sandy or alkaline places, on plains and hillsides, lower Arid Transition Zone to Lower Sonoran Zone; 

 eastern VV'ashington southward east to the Cascade- Sierra Nevada Divide to the Mojave Desert, California, east 

 to Idaho, Nevada, Wyoming, and Utah. Type locality: "Rocky Mountains." Collected by Nuttall. May- Aug. 



2. EUPLOCA Nutt. Trans. Amer. Phil. Soc. II. 5: 189. 1837. 



Low branching usually pubescent annuals with alternate leaves. Flowers scattered, 

 solitary in the leaf-axils. Calyx-lobes 5. Corolla salverform, the tube cylindric, naked in 

 the throat, limb 5-angled, stron.s:ly plicate in the bud. Stamens 5 ; anthers slightly coher- 

 ing by their minutely bearded tips. Ovary 4-celled; style long and filiform; apex of the 

 stigma truncate and bearded with a tuft of penicillate bristles. Fruit didymous, the two 

 lobes each splitting into 2 hemispherical 1-seeded nutlets. [Name Greek, meaning well 

 and a woven thing.] 



A monotypic genus of the arid southwestern United States and Mexico. Type species, Euploca convolvulacea 

 Nutt. 



1. Euploca convolvulacea subsp. californica (Greene) Abrams. 

 Bindweed Heliotrope or Euploca. Fig. 4166. 



Heliotropium californicum Greene, Bull. Calif. Acad. 1 : 202. 1885. 



Heliotropium convolvulacexim var. californicum I. M. Johnston, Contr. Arnold Arb. No. 3: 83. 1932. 



Euploca alhiflora var. californica Jepson & Hoover in Jepson, Fl. Calif. 3: 299. 1943. 



Stems branched and usually spreading, 4-10 cm. high, the entire plant more or less densely 

 hispid with both spreading and upwardly appressed whitish hairs pustulate at the base. Leaves 

 varying from broadly ovate to narrowly lanceolate, commonly ovate, 1.5-3 cm. long, acute or 

 abruptly short-acuminate at apex, rounded to acutish at base, grayish green and densely hispid 

 on both sides, the hairs except on the margin more or less appressed ; flowers borne solitary near 



