CONTRIBUTIONS TO WESTERN BOTANY. 21 



and minute teeth, narrow, curved, nearly sessile; stems angled. 

 Mojave region to San Bernardino, Cal., Jones, Parish. 



A. argentea Nutt. A. nodosa Greene Pitt, i 40, A. volutans 

 A. Nelson. 



Var. comuta (Jones Cont. 7 718), A. comuta, Jones 1. c. 



Var. Hillmani. 



Bracts panduriform to orbicular, 2-4 lines wide, with triangu- 

 lar and very short and sharp processes ; leaves broadly lanceolate, 

 6 lines long, nearly sessile, with a cuneate base ; widely spreading, 

 much branched, low, 6 inches high. Reno, Nevada, Hillman. 



A. Nelsoni 



Fruiting bracts panduriform to orbicular. 2-4 lines wide, with 

 very broad and green margins which are simply wavy or erose 

 along the top and extending down the sides, sides also cleft to. the 

 body of the seed into one or more truncate lobes, sides mostly un- 

 appendaged, but occasionally with simitar but shorter processes. 

 No. 531 1 A. Nelson, Howell Lake, Wyo., Sept. 13, 1898, distrib- 

 uted as A. expansa. This is apparently a very good species, but it 

 may prove to be only an aberrant form. 



A. sabulosa. 



Low and tufted shrubs with the habit of A. acanthocarpa var. 

 cuneata, woody only at base where the stems are decumbent, aboyt 

 I foot high, stems sparingly branched at base, round, not spines- 

 cent, herbaceous, very leafy : leaves ovate to obovate or oval, 

 about I inch long, rounded at tip and cuneate below, entire, thick, 

 on short petioles, white-scurfy ; flowers in simple and leafy panicles 

 with appressed branches : bracts at least the central ones pediceled, 

 panduriform, flat, about 3 lines wide, very shortly-triangular 

 toothed nearly to base, face without appendages, united one-third 

 the way up. This bears the same relation to A. acanthocarpa var. 

 cuneata that A. pabularis does to A. Nuttallii, appearing to be v^ry 



