42 CALLITRICHACEAE 



united, dorsal distinct ; cyathia solitary ; involucres campanulate, appressed-pubescent to glabrate, 

 1.5-2 mm. in diameter; glands dark red-purple, transversely oblong, 0.7-1.2 mm. long; fifth 

 gland usually absent ; sinus U-shaped, little depressed, hairy ; appendages absent to conspicuous, 

 white, glabrous, entire to lobed ; staminate flowers 22-25 ; capsule strigose, 2 mm. long, sharply 

 3-angled, deltoid-ovoid; seeds white, 1-1.3 mm. long, slenderly ovoid, circumferentially 4-5 round- 

 ridged. 



Dry desert washes and flats. Lower Sonoran Zone; Colorado Desert, California, east to Arizona, south to 

 Lower California and Sinaloa. Type locality: Sonoita Creek, Santa Cruz County, Arizona. Oct.-April. 



28. Euphorbia melanadenia Torr. Squaw Spurge. Fig. 3060. 



Euphorbia melanadenia Torr. Pacif. R. Rep. 4: 135. 1857. 



Euphorbia cinerascens var. appendiailata Engelm. Bot. Mex. Bound. 186. 1859. 

 Euphorbia polycarpa var. vestita S. Wats. Bot. Calif. 2: li. 1880. 

 Chamaesyce aureola Millsp. Field Mus. Bot. Ser. 2:406. 1916. 



Perennial, stems ascending or erect, to 20 cm. long, closely tomentose, glabrate. Leaves 3-9 

 mm. long, ovate to narrowly oblong, inequilateral, entire, closely and often hoary tomentose ; 

 stipules linear, hairy, ventral united, dorsal distinct ; cyathia solitary ; involucres open-campanu- 

 late, 1.2-1.5 mm. in diameter, appressed short-tomentose ; glaands dark reddisli purple, 0.4-0.6 

 mm. long, transversely oblong ; fifth gland absent ; sinus U-shaped, not depressed, densely hairy ; 

 appendages rarely absent, usually conspicuous, white, glabrous, crenate to subentire ; staminate 

 flowers 15-20; capsule sharply 3-angled, very short-tomentose, ovoid, 1.5-1.7 mm. long; seeds 

 white to brownish, 1.2-1.5 mm. long, ovate, sharply quadrangular, facets smooth or slightly 

 wrinkled. 



Dry hillsides. Upper Sonoran Zone; Los Angeles and San Diego Counties, California, east to Arizona and 

 south to Lower California and Sonora. Type locality: "San Gabriel," California. Actually probably the foot 

 of the San Gabriel Mountains a few miles north. Feb.-Nov. 



29. Euphorbia vallis-mortae (Millsp.) J. T. Howell. Indian Spurge. Fig. 3061. 



Chamaesyce vallis-mortae Millsp. Field Mus. Bot. Ser. 2:403. 1916. 

 Euphorbia vallis-mortae J. T. Howell, Madrono 2: 19. 1931. 



Perennial, hoary tomentose throughout; usually forming a dense rounded plant up to 15 

 cm. high. Leaves 4-8 mm. long, suborbicular to oblong-ovate, entire ; stipules densely hairy, 

 filiform, ventral united, dorsal distinct ; cyathia solitary ; involucres campanulate, 2 mm. in 

 diameter, tomentose ; glands reddish, transversely oblong, to 1 mm. long ; fifth gland absent ; 

 sinus U-shaped, with long erect hairs ; appendages conspicuous, white, entire to crenulate, 

 pubescent beneath and on the margins and sparsely so above; staminate flowers 17-22; capsule 

 sharply 3-angled, tomentose, globose, 2 mm. long; seeds white, 1.4-1.7 mm. long, sharply 

 quadrangular, facets smooth. 



Sandy desert. Lower Sonoran Zone; Inyo and Kern Counties, California. Type locality: near Indian Wells, 

 Mojave Desert, Kern County, California. May-Oct. 



30. Euphorbia supina Raf. Spotted Spurge. Fig. 3062. 



Euphorbia supina Raf. Amer. Month. Mag. 2: 119. 1817. 



Euphorbia maculata L. sensu American authors. 



Euphorbia depressa Torr. Cat. PI. N.Y. 45. 1819. 



Chamaesyce supina Moldenke, Annot. & Class. List Moldenke Nos. 135. 1939. 



Annual, stems usually prostrate, villous, 10^5 cm. long. Leaves 4-17 mm. long, oblong- 

 ovate to oblong-linear, larger inequilateral, sparsely villous, often glabrate above, serrulate ; 

 stipules distinct, 2-3-parted, villous ; cyathia solitary but mostly borne on short congested lateral 

 branches; involucres 0.8 mm. in diameter, villous, obconical ; glands 0.15-0.25 mm. long, trans- 

 versely elongate ; fifth gland filiform ; sinus U-shaped, depressed, long-hairy ; appendages narrow, 

 white, glabrous, irregularly crenulate ; staminate flowers 2-5 ; capsule sharply 3-angled, strigose, 

 often partially glabrate, globose, 1.4 mm. long; seeds whitish brown, 1-1.2 mm. long, ovate, 

 sharply quadrangular, facets with irregular transverse ridges often slightly including the angles. 



A mainly urban weed introduced from the eastern United States; western Oregon, cismontane California. 

 Type locality: "Very common on the downs and seashores of Long-Island, north and south, also in New-Jersey, 

 Sandy-Hook, &c." June-Sept. 



Family 80. CALLITRICHACEAE. 

 Water-starwort Family. 



Aquatic or rarely terrestrial herbs, with very slender stems. Leaves opposite, 

 entire, spatulate or linear, without stipules. Flowers small, axillary, perfect or mo- 

 noecious, with or without 2 sac-like bracts. Perianth wanting. Stamen 1, with a 

 filiform elongated filament, and cordate 2-celled anthers opening by longitudinal 

 slits. Pistil solitary, sessile or peduncled ; styles 2 ; ovary 4-celled, with a single 

 ovule in each cavity. Fruit compressed and lobed, the lobes more or less winged or 



