242 BOTANY. 



smooth, reddish capsules, the black, scantily villous scales, and the leaves 

 colored alike on both sides ; aments somewhat as in S. Novce Anglice, var. 

 pseudo-myrsinites, Anders., but that has beaked capsules and glabrous, 

 crenate leaves, which are membranous in texture and prominently reticu- 

 late-veined. 



Salix reticulata, L. (Watson, vol. v, King's Report, p. 327 ; Porter, 

 FL Col. 128).— Half Moon Creek, Colorado, at 13,000 feet elevation (830). 



Populus monilifera, Ait, — Nevada, 



Populus balsamifera, L., var. angustifolia, Watson. — Nevada and 

 Utah, and San Luis Valley and Denver, Colo. (833, 834). Var. candicans, 

 Gray, Colorado (835). 



Populus tremuloides, Michx. — San Francisco Mountains, Arizona ; 

 also South Park, Colorado (832). 



Populus angulat^, Ait. — Denver (831). 



EUPHORBIACEiE. 



By Dr. George Engelmanw. 



Croton corymbulosus. — Many erect stems from a ligneous base, a 

 span to a foot high, simple below, branching upward; stipules subulate, 

 deciduous; petioles about half as long as the oval or oblong, mostly acutish, 

 leaves, which are |-1 J' long, the lowest ones broader and shorter and often 

 acutish at base, all triplinerved at base, penninerved upward, whitish below, 

 greenish-gray above; stellate hairs slightly united to scales above, almost 

 free and loose below; inflorescence short, loose-flowered, corymb-like, 6-8" 

 wide, mostly monoecious; pedicels 2-3" long, much longer than the 

 flowers; male flowers with 5 spatulate or lanceolate bearded petals alter- 

 nating with the 5 lobes of the disk; 6-13 stamens with bearded filaments; 

 female flowers mostly apetalous; styles bifid to below the middle or usually 

 to the base, and together with the ovary and the oblong (3" long) capsule 

 stellate scaly; seeds linear-oblong, 2" long, delicately punctate-reticulate. — 

 Camp Bowie, New Mexico, Rothrock, 1874 (506). Through Western 

 Texas (Wright, 641, 1805) into Mexico (Saltillo and Buena Vista, Gregg, 71, 

 288). This species was first described by Torrey in Bot. Mex. Boundary, 

 p. 194, under the name of C. Lindheimerianus, in which Midler, DC. Prod. 

 15, 2, 579, followed him. But Scheele's plant thus named and described in 



