BOTANICAL EErOKT. 



445 



Tliis Is tlie ^*Wild Siige" of tlie Upper MLssouri (above tlie mouth uf tlio Yellow- 

 stone) and the Yellowstone Rivei'j and of the Laramie riaiiis, T)ut it does not seem to 

 occur west of the Kocky Mountains, as Torrey and Gray (/. c.) already state, and 

 Nuttall (7. c\) must have confounded it with otlier species, when he contends tliat it is 

 ^'still more abundant on the barren plains of the Columbia Ivivcr", and that it grows 

 6 to 8 or 12 feethin;li. 



Artemisia tridentata, NuftaU ui Trans. Amer, PhU. Soc. (n. scr.) 7, p. 398; Torrey 

 and Graj/j Fl 2, jh 418. — Trunk, bark, and wood very similar to that of tlic last species, 

 but trunk often larger, and usually even more twisted and knotty, with very numerous 

 short and stunted branches, whicli are repeatedly divided into a great many sinnlli^r 

 branchlets; ultimate annual branchlets fiiscicled, erect, oidy 3-G inches long, canescent 

 or silvery, very leafy at base, rather naked uj»wanl, bearing strict, rather compact, pan- 

 iculate spikes, composed of sessile or usually pedunculate spikelcts or glomerules of 3 

 to G or 8 sessile heads. Leaves silvery-Avhite on both surfaces, crowded at the base of 

 the branches, and often fascicled on short or stunted sterile branches, narroA\ly Avcdge- 

 shaped, lA-2 lines wide at the obtuse tridentate or trilobcd end, narrowed down into 

 a more or less distinct petiole; usually 3-6, rarely 8, lines long. Iniiorcsccnce inter- 

 spersed with short and narrow, undivided, cuneate or spatulate obtuse leaves, TTead 

 of flowers narrow, obovoid, nearly 1^ linos long, not much more than hnlt^ as wide, 

 with short and obtuse, canescent, exterior scales, and longer, scarious, interior scales, 

 ciliate on the sides. Flowers in some specimens 3, in others often 4-5 in each head, 

 all perfect, scarcely more than 1 line long; ovary quite glandular and witli the odor 

 of turpentine. 



This is the ^'Wild Sage" of Utah, and, perhaps, of the whole region west of the 

 Rocky Mountains, where it seems to supplant the more eastern A, cana. Nuttall, who 

 first desciibed it, calls it a shrub about a foot high, and as such it appears in the 

 mountains of Colorado; but in Utah it is the largest and most abundant species, 

 usually 2-4 feet high, rarely attaining a height of 6 feet, and then not straight, and 

 with trunks of 3-6 inches diameter; sometimes the smallest bushes have trunks fully 

 as thick as the tallest ones, short and chunky. East of the mountains, in the range of 

 A. cana^ it ever remains an inconspicuous shnib, lost among the more common species, 

 Near Camp Floyd, specimens were collected bearing -white tomentosc excrescences of 

 the size of a pea, or larger, undoubtedly galls caused by the sting of insects ; the same 

 have been observed on this species in Colorado. 



The otlier species of Arkmlsia collected by the expedition were A. Canadensis^ 

 Michx., at Bridger's Pass; A. Ludovlciana, Nutt., at Sweetwater, Bridger's Pass, Round 



Prairie, etc.; A, dracuncuhldes^ Pursh, on the Sweetwater; and^. friukla, Willd., on the 

 Upper Sweetwater River. 



chp:nopodiace^. 



Sakcobatus veemiculatus, Torrey in Emory's Itejport (1848), jp. 149. Batis (?) 

 ver'miculata, -ffooAer, Flor. Bor.'Am. 2,^. 128 (1840); Sarcobatus Maximiliani, Xees in 

 Fr, Maximil Trai\ EnyL ed. ih 518 {ex Torrey)^ Seiilcrt in Bot Zeiiiing^ 18-44, |). 753, ciun 

 tah.j LindUy in Jloolxr^ Lond. Jonrn. Bot, IV^ p. 1 (1845); Fremontia vermicularis, 



