Thompson — Four New Plants from Mexico. 23 



Seduin versadeose n. sp. 



Perennial, much branched from the base, branches at first short and 

 with the closely set leaves forming rosettes, later elongating and 

 reaching 2 dm,, decumbent with ascending tips, rooting at the nodes, 

 pubescent, leafy. Leaves alternate, sessile, obovate-cuneate to obcor- 

 date-cuneate, 9-18 mm. wide, 1.3-2.5 cm. long, fleshy, thick, flattened, 

 apex usually deflexed, rounded margins slightly upturned, pubescent, 

 light green, frequently red margined at the apex or the red also 

 extending downward on the under surface beneath the apex. Flower 

 stalks upright, terminating the branches, 3-5 cm. long, leafy-bracteate ; 

 these from triangular-obovate with obtuse apex to broadly lanceolate 

 with acute apex, grading into the bracts of the inflorescence, glabrous 

 and slightly glaucous. Inflorescence divided into two or three secund 

 racemes, leafy-bracteate; bracts broadly lanceolate, fleshy, 2-3 mm. wide, 

 4-6 mm. long, glabrous, slightly glaucous; pedicels about 3 mm. long; 

 sepals distinct, lanceolate, very unequal, little shorter than the petals, 

 fleshy, convex on both surfaces, sharply acute; spreading nearly hori- 

 zontally in flower, nearly erect in fruit, slightly incurved, scarcely dis- 

 tinguishable from the bracts; flower buds purplish-pink, petals spread- 

 ing, later becoming recurved, lanceolate, mucronate, 2 mm. wide, 

 5-6 mm. long, light purplish-pink to almost white, keeled on the back, 

 channeled down the face; stamens obliquely to horizontally spreading, 

 one-half the petal length, those opposite the petals inserted a little 

 above the base, those alternate inserted at the base, filaments white, 

 anthers ovoid, abruptly acute, bright rose-red; carpels distinct, erect, 

 styles tapering to the stigma, slightly spreading in flower, erect in 

 fruit.— Plate XII. 



Collected by Dr. William Trelease, February, 1905, at 

 Versada, half way between El Parian and Tomellin, Oax- 

 aca, Mexico. (M. B. G. No. 47/05.) 



A study of the plant in connection with Britton and 

 Eose 's recent monograph of the American representa- 

 tives of this order would throw some doubt on its generic 

 position. The rosette arrangement of the pubescent 

 leaves and the erect carpels very strongly suggest affinity 

 with the genus Sedastrum, but the ultimate elongation of 

 the rosette into a leafy stem and the production of the 

 inflorescence from its apex are characters not thus far 

 met with in that genus. The form of the inflorescence 

 would place it equally well in either Sedastrum or Sedum. 

 As between these genera there is a discrepancy in the 

 above cited monograph. In the generic characters given 

 for Sedastrum the inflorescence is described as ^'more or 



