OP ARTS AND SCIENCES. 273 



Sedum Pringlei. Annual, glabrous ; stems 2 or 3 inches high, 

 from a slender subtuberous root, leafy, several times dichotomously 

 forked above : leaves sessile, oblong-lanceolate, obtuse, 3 lines long : 

 flowers few upon the branches, very shortly pedicellate : sepals about 

 a line long, the lanceolate acutish pale-rose petals twice longer : fila- 

 ments subulate, shorter than the petals ; scales oblong-spatulate, firm 

 and thick : carpels erect, acutish, the styles very short. — In thin soil 

 on hillsides near Cusihuiriachic, Chihuahua; C. G. Pringle (n. 1239), 

 Aug., 1887. 



Sedum Chihuahuense. Annual, glabrous ; stems erect from a 

 small oblong tuber, 3 to 5 inches high, repeatedly dichotomous above : 

 leaves sessile, oblong or oblong-lanceolate, obtuse, 3 or 4 lines long : 

 flowers sessile or very shortly pedicellate upon the slender branches ; 

 sepals broadly oblong, obtuse, 1 becoming H lines long; petals white, 

 oblanceolate, 2 lines long : stamens included ; scales clavate, slender : 

 carpels shorter than the petals, attenuate above, at length divergent. 

 — Nearly allied to the last and to S. fuscum, Herasl. In thin soil 

 on rocky ledges in the Sierra Madre, Chihuahua ; C. G. Pringle 

 (n. 1240), Sept., 1887. 



Sedum Madrense. Perennial, with a somewhat creeping root- 

 stock, the branching stems 6 inches high or less, leafy, glabrous : 

 leaves numerous, sessile, ligulate-oblanceolate, obtusish, 3 or 4 lines 

 long : flowers shortly pedicellate in loose spreading cymes : sepals 

 oblong, obtuse, 2 lines long ; petals purple, linear-lanceolate, obtuse, 

 3 to 8-J lines long : stamens included, the scales very short and trun- 

 cate-flabelliform : carpels equalling the petals, acuminate with the 

 slender styles, becoming divaricately divergent. — On dry ledges in 

 the Sierra Madre, Chihuahua ; C. G. Pringle (n. 1241), Oct., 

 1887. 



Sedum puberulum. Rough-puberulent throughout; stems from 

 a dense cluster of fibrous and fleshy roots, slender, simple or once 

 forked, 1 to 3 inches high : leaves sessile, oblong or the upper linear- 

 oblong, acute or acutish, 3 to 5 lines long : flowers few, sessile or 

 shortly pedicellate ; sepals narrowly oblong, 2 or 3 lines long ; petals 

 white, oblanceolate, acute, 3 lines long, scarcely exceeding the sta- 

 mens ; scales short, quadrangular : carpels erect, acuminate with slen- 

 der styles. — On shaded cliffs in the Sierra Madre, Chihuahua ; C. G. 

 Pringle (n. 1242), Oct., 1887. 



Rotala Mexicana, Cham. & Schlecht. The leaves all opposite 

 and the calyx appendaged at the sinuses. — In wet places on the plains 

 near Guerrero, Chihuahua; C. G. Pringle (n. 1365), Sept., 1887. 

 vol. xxiii. (n. s. xv.) 18 



