Part 1, 1905] CRASSULACEAE 59 



4. Sedastrum ebracteatum (Mog. & Sesse) Rose. 



Sedum ebracteatum M05. & Sess^, in DC. Mem. Crass. 37, pi. 6, B. 1828. 



Leaves in dense sessile rosettes, obovate or spatulate, flattened but fleshy, 2-3 cm. 

 long, either ciliate on margins, or both surfaces (at least when young) covered with stiff 

 hairs. Flowering stems rather weak, about 3 dm. high, ascending or procumbent, more 

 or less mottled with red, pubescent, leafy, somewhat branching ; stem-leaves somewhat 

 similar to basal ones but broader at base ; flowers sessile or short-pedicelled ; sepals 5, very 

 unequal and leaf-like ; petals 4 or 5, whitish, the midrib greenish,, spreading when first 

 opening, longer than the sepals ; stamens 8 or 10 ; hypogynous scales thickish, ligulate. 



Type locality: Mexico. 

 Distribution : Hidalgo. 

 Illustration : DC. loc. cit. 



5. Sedastrum rubricaule Rose, sp. nov. 



Stems about 30 cm. high, somewhat pubescent, greenish below, purplish above. Basal 

 rosettes dense ; leaves ovate, thick, rather obtuse ; stem-leaves acutish, bright green ; flowers 

 on ultimate branches 3 or 4, sessile; calyx green, cleft to near the middle; petals broadly 

 ovate, white; stamens erect ; anthers yellowish ; carpels erect. 



Collected by Dr. B- Palmer near Concepcion del Ore, State of Zacatecas, Mexico, November 

 22, 1902 {no. 386). These specimens flowered in Washington in. October and November, 1903. 



6. Sedastrum chapalense (S. Wats.) Rose. 



Sedum chapalense S. Wats. Proc. Am. Acad. 22 : 411. 1887. 



Stems about 10 cm. high, much branched, yellowish-green, glabrous. Leaves slightly 

 pubescent, those of the sterile shoots obovate or ovate, acutish, 12 mm. long, the stem- 

 leaves rather thin for the genus ; flowers sessile, arranged along one side of the axis ; osCiys. 

 5-parted, its lobes unequal, obtuse or acute ; petals white, oblong-ovate, acute, 4 mm. long ; 

 scales small. 



Type locality : Chapala, Jalisco, Mexico. 

 Distribution : Jalisco. 



7. Sedastrum incertum (Hemsl.) Rose. 



Sedum incertum Hemsl. Diag. PI. Nov. 1 : 11. 1878. 



Stems rather thick, either clambering or hanging over rocks, 3-4 dm. long. Leaves 

 fleshy, slightly pubescent, broadly ovate, in herbarium specimens with nearly rounded 

 apex, 2-3 cm. long ; flowers in rather short interrupted spikes ; calyx-lobes ovate, obtuse ; 

 petals white drying with a yellow tinge. 



Type locality : Valley of Mexico. 

 Distribution : Valley of Mexico. 



24. TETRORUM Rose, gen. nov. 



Low, diffuse annuals. Calyx minute, its lobes broader than high. Petals purple, 

 obtuse, distinct. Stamens 10. Scales large. Carpels 4, widely spreading in age, distinct, 

 constricted at base, many seeded. Style minute. 



Type species, Sedum pusillum Michx. 



1. Tetrorum pusillum (Michx.) Rose. 



Sedum pusillum Michx. Fl. Bor. Am. 1 : 276. 1803. 



Annual, pale-green, glabrous. Stems usually branched near the base, leafy above, 

 5-30 cm. high ; leaves terete or nearly so, linear, sessile, obtuse, 1-2 cm. long ; branches 

 of the cyme 2-6 cm. long ; pedicels 2-6 mm. long ; calyx- segments linear to linear- oblong, 

 obtuse; petals purple, oblong, scarcely twice as long as the calyx-segments; follicles 

 slender, about 5 mm long, tapering into the subulate styles. 



Type locality : Flatrock, North Carolina. 



Distribution : On mountain rocks, North Carolina and Georgia. 



