258 PITTONIA. 
also their marked characters. The specimens do not show 
cernuous heads; yet Mr. Macoun labelled them B. cernua. 
Y B. GLAUCESCENS. Stout, often freely and widely branched, 
1 to 24 feet high, glabrous, the terete stem glaucescent, its 
internodes short and foliage ample: leaves elliptic-lanceo- 
late, the largest 4 to 6 inches long, closely striate-nerved be- 
tween midnerve and margin and as closely serrate: heads 
large, hemispherical: outer involucre surpassing the rays; 
these many (occasionally wanting): disk-corollas exceeding 
the awns, their tube longer than the short cylindric limb: 
achenes mostly 4-angled and 4-awned, the angles more or 
less corky, the main ones also tuberculate under each hair, 
the other two tuberculate but not bearing hairs. 
In so far as I can recognize it in the herbarium this is 
peculiar to the western mountain districts and the plains 
adjacent, but beginning in Kansas, perhaps in Missouri. 
The following specimens may be cited. Kansas, Saline Co., 
Mark White, 1898; Pratt Co., Carleton, 1891; Kiowa Co., 
L. F. Ward, 1897; Atchison Co., Hitchcock, 1896 (n. 735). 
Colorado, H. G. Smith, 1888. Wyoming, A. Nelson, 1892 
(n. 101). Utah, Kingston, M. E. Jones, 1894 (n. 5,978). 
The species forms some part of Mr. Wiegand's B. cernua, 
var. elliptica. 
* B. toncnopHytia. ‘Taller than the last, often 3 or 4 feet 
high, less branched and the branches ascending; leaves 
larger, often 6 or 8 inches long, thinner, more exactly 
lanceolate, more remotely serrate and less notably striate- 
veiny: stem green, not glaucescent, sometimes a little scab- 
rous: bracts of outer involuere many, oblong, about as long 
as the rays, these golden-yellow: disk-corollas surpassing 
the awns: achenes mostly 4-awned, the principle angles 
