NYCTAGINACEAE 451 



2. CLADOTHRIX Nutt. 



Stellate-pnlipscent annuals or woody-based perennials with opposite leaves. 

 Flowers axillar.y, solitary or in small glonierules. perfect, subtended by 3 

 small bracts and by foliaceous involueral bracts. Sepals 5. equal, thin, 

 pubescent. Stamens 5, arising from the margin of a short cup-shaped 

 hypogyiious disk, with 5 short teeth alternating with the filaments. Aehene 

 subglobose, indehiscent. — Species 3, southern United States and Mexico. (Greek 

 klados, branch, and thrix. hair, in reference to the stellate covering.) 



1. C. oblongifolia Wats. White-woolly perennial; stems widelj' branch- 

 ing, forming low broad mound-like plants 9 to 15 inches high and IV'o to 3 

 feet broad ; leaves roundish ovate, obtuse, 3 to 10 lines long, shortly petioled ; 

 uivolucral bracts united and forming definite involucres; involucres panicu- 

 lately disposed, subsessile or shortly peduncled, their tubes oblong-turbinate, 

 1 to li-o lines long, their lobes 3, foliaceous, round-ovate. 1 to 2 lines long; 

 sepals ovate-lanceolate, 1 line loug. 



Sandy washes ; Colorado Desert and eastern Mohave, north into Inyo Co. 

 Arizona, southern Nevada. 



Loes. — Milpitas, Colorado River, Jepson 5283; Salton, Parish; Bagilacl, T. Brandegee ; Death 

 Valley, ace. CoviUc. Ash Milws., Nev., Purpus 602.5. 



Kefs. — Cl.\dothrix oblongifolia Wats. Proc. Am. Acad. 17: 376 (1882), type spms. from 

 the Colorado River (Chimney Peak, Xtirberri/, and Yuma, Prinqlt) and the ilohave Desert, 

 Warm Sprs., S. B. <J- W. F. Parish 1346; Cov. Contrib. U. S.' Nat. Herb. 4: 179 (1893). 

 C. cryptantha Wats. Proc. Am. Acad. 26: 125 (1891), based on spms. bv Parry (e. Colorado 

 Desert) and by Orcutt 2186 (Carrizo Creek, San Diego Co.); Parish, 'Zoe, 5: 113 (1901). 

 C. lanuginosa Wats. Bot. Cal. 2: 43 (1880), not Nutt. With each flower-cluster set in an in- 

 volueral cup, C. oblongifolia is sharply separated from C. lanuginosa Nutt., which has solitary 

 flowers and its involueral bracts quite distinct. The latter species occurs in Arizona and may 

 yet be found in southeastern California. 



Alternanthera achyrantha R. Br. Prodr. 1: 417 (1810). Prostrate annual 

 with opposite leaves; leaves broadly ovate or obovate. shortly acute or mucro- 

 nate. 5 to 11 lines long, cuneately narrowed at base into a petiole; flowers per- 

 fect, in short white spikes; spikes dense, mostly axillary, solitary or clustered, 

 3 to 6 lines loug; sepals 5. lanceolate, unequal. 2 more carinate-concave, all 

 woolly on the back with barb-tipped hairs; stamens 5, with 5 alternating 

 sterile filaments, all united at base into a cup-like disk; aehene flattened, 

 indehiscent. — Native of jMexico, locally introduced at Los Angeles (Erythea, 

 1: 99). 



NYCTAGINACEAE. Four-o'clock Family. 



Ours more or less succulent herbs or low shrubs with opposite entire leaves 

 and commonly swollen joints. Flowers perfec^t, regular, subtended by bracts 

 which often form a calyx-like involucre. Bracts or involucres often colored. 

 Calyx plicate in the bud. tubular, colored like a corolla and very delicate. 4 

 or 5-lohed. the lower part of its tube circumscissile and leaving a persistent 

 base which is closely constricted over but not attached to the superi(U' ovary. 

 Corolla none. Stamens in ours 3 to 5 (or 7), mostly unequal, hypogynous 

 (or perigynous in Abronia). Ovary 1-celled, 1-ovuled; style and stigma 1. 

 P'ruit an aehene, closely invested by the base of the calyx-tube, which be- 

 comes very much hardened and is often striate, ridged, or winged. Embryo 

 mostly coiled, with mealy endosperm ; cotyledons 2, or only 1 in Abronia b.y 

 reduction. — Genera 20 and species about 200; all continents but mainly Ameri- 

 can. 



Bibliog. — Gray, A., Some new Gen. and Sp. of Nyctaginaceae, prin. coll. in Tex. and New 

 Mex. (Am. Jour." Sci. ser. 2, 15: 259-263, 319-324,-1853). Rydberg, P. A., Nyctaginaceae of 

 Rocky Mt. Reg. (Bull. Torr. Club, 29, 680-693,— 1002). .Tones. M. E.. Nyctaginaceae of the 

 Great Plateau (Contrib. 10: 34-54,-1902). Standley, P. C, Allioniaeeae of the United States 



