BORAGE FAMILY 533 



Corolla white, sometimes cream-colored or pale yellow in the throat; 

 mostly annuals. 

 Calyx circumscissile. 16. Greeneocharis. 



Calyx not circumscissile, or rarely so in Plagiobothrys. 



Nutlets keeled on the ventral side, not grooved or if so the 

 groove enclosing the keel; calyx and pedicels persistent. 

 Lower leaves opposite, not forming a rosette; nutlets at- 

 tached by a scar or groove, not carunculate, mostly 

 erect; corolla-tube often yellowish within. 



17. Allocarya. 



Lower leaves alternate; nutlets attached above the base to 

 a caruncle or thickened scar, oblique or incurved; 

 corolla white throughout. 



Nutlets with the caruncle borne on a stipe-like base; 

 lowest leaves not in a rosette. 



18. Echidiocarya. 



Nutlets with the caruncle borne in a hollow or trans- 

 verse groove; lowest leaves mostly in a rosette. 



19. Plagiobothrys. 



Nutlets not keeled on the ventral side, but grooved above the 

 basal scar and attached from the scar along the 

 ventral groove to the middle or apex; calyx and pedicels 

 falling away with the nutlets; corolla-throat with crests; 

 leaves all alternate. 

 Annuals. 



Stems dichotomously branched; racemes with each 

 flower in the axil of a foliaceous bract; style 

 dilated in fruit; gynobase columnar. 



20. Eremocarya. 

 Stems branched but not dichotomously; racemes spike- 

 like and bractless or few-bracted, rarely bracted 

 throughout, if so, the bracts unequal; style not 

 dilated in fruit; gynobase subulate. 



21. Cryptantha. 



Perennials, often cespitose. 22. Oreocarya. 



Corolla bright yellow or orange, the throat open or inconspicuously con- 

 stricted, not crested. 23. Amsinckia. 



Fruiting calyx greatly enlarged and membranous. 24. Asperugo. 



Calyx armed with prickles, irregular and bur-like in fruit. 25. Harpagonella. 



1. COLDENIA L. Sp. PI. 125. 1753. 



Low herbaceous or suffrutescent plants, canescent or hispid. Leaves small, entire, 

 usually strongly veined. Flowers small, generally white, sessile and solitary or often 

 clustered in the axils of the leaves, 4-merous or commonly 5-merous. Calyx deeply lobed 

 into narrow segments. Corolla with a short tube, naked or scaly within ; lobes short and 

 rounded, imbricated. Stamens 4—5, included, their filaments adnate to the corolla-tube. 

 Style 2-cleft or 2-parted. Ovary 2-celled or sometimes 4-celled by the septum-like 

 placentae, entire or 4-lobed. Fruit with a thin usually dry exocarp, separating into 4 

 nutlets. [Name in honor of Dr. Cadwallader Colden, Colonial Lieutenant-Governor of 

 New York and correspondent of Linnaeus.] 



A genus of about 20 species, native of the western hemisphere, with one species also in the tropics of the 

 Old World. Type species, Coldenia procumbens L. 



Fruit merely 4-sulcate, bearing the style in its rounded summit; stems not dichotomous; leaves not conspicuously 



veined; perennial, woody at base. 1. C. canescens. 



Fruit deeply 4-lobed, bearing the style between the lobes; stems dichotomously branched. 

 Plants perennial, stems woody below or from a stout woody root; corolla bluish. 



Leaves with 4-6 rib-like veins, the surface of at least the younger ones distinctly plicate, densely white- 

 silky pubescent, margin entire. 2. C. plicata. 



Leaves 3-4-veined, the veins somewhat irregular, not plicate, margin somewhat sinuate. 



3. C. Palmeri. 



Plants annual, prostrate; corolla pink or white. 4. C. Nuttallii. 



1. Coldenia canescens A. DC, Shrubby Coldenia. Fig. 4162. 



Coldenia canescens A. DC. Prod. 9: 559. 1845. 



Coldenia canescens var. subnudata I. M. Johnston, Proc. Calif. Acad. IV. 12: 1137. 1924. 



Low, much-branched shrub often forming mats, 5-15 cm. high, the older main branches 



woody and becoming stout and gnarled. Leaves white-tomentose with intermingling short- 



villous hairs, oblong-lanceolate to ovate, 6-10 mm. long, plane or commonly with the entire 



margins revolute, longer than the petioles ; calyx 4-6 mm. long ; corolla white, 6-7 mm. long ; 



style slightly exserted above the calyx-lobes ; fruit depressed-globose, about 2 mm. wide, glabrous 



or sparsely hairy at the summit. 



Rocky ridges or benches, Lower Sonoran Zone; eastern parts of the Colorado Desert, Riverside and Im- 

 perial Counties, California, east to Texas and south to Lower California and northern Mexico. Type locality: 

 between Santander and Victoria, Tamaulipas, Mexico. March-May. 



Coldenia canescens var. pulchella I. M. Johnston, Journ. Arnold Arb. 20: 379. 1939. Flowers larger; 

 corolla 9-12 mm. long with the limb 5-8 mm. in diameter, blue or lavender. A local variation found in the 

 Chocolate Mountains, Imperial County, California, and adjacent Arizona. Type locality: Kofa Mountains, 

 Yuma County, Arizona. 



