4 . Colorado Plants. | ZOE 
Mr. Alfred Wetherill, who discovered it, reports it also 
from Southeastern Utah in similar situations. 
ARGEMONE. ‘There seems to be doubt as to the existence of 
Argemone hispida Gray as a species, and in Colorado, if it has 
ever previously been collected, it has been merged into A7gemone 
platyceras Link & Otto. It is excluded from both Patterson’s 
and Oyster’s check lists, but whether included under 4. Alaty- 
cerasor A. Mexicana var. albiflora has not been learned. Judging 
from the specimens of 4. Mexicana var. albiflora now in the 
herbarium of the California Academy of Sciences, 4. platyceras 
is much nearer A. Mexicana var. albiflora than A. hispida. 
They are alike in the stem and foliage, glabrous and glaucous, 
except for the spines which are scattered on the stem and on the 
veins and margins of the leaves. The veins are also outlined 
with white, immature pods seem the same; the stamens differ 
slightly, A. Mexicana var. albiflora having broad filaments 
abruptly narrowed to the anther; A. platyceras with filaments 
narrower and tapering to the anthers which are longer and 
narrower than those of A. Mexicana. There is some variation 
in A, platyceras in the manner of branching, size of the pods, 
and number of spines. There are forms that closely resemble 
A. corymbosa, differing chiefly in having larger pods and the 
leaves longer, with deeper lobes and blunter at the apex. 
Argemone hispida Gray. ‘This is distinct from both A. Mext- 
cana var. albiflora and A. platyceras, and shows so little variation 
that specimens from Colorado and California have no appreciable 
difference and agree with the original description as given in 
Gray’s Plante Fendlerianz. It differs most noticeably from the 
other two in the pale green foliage densely covered with short 
crimped bristles, short spines on the margins and veins of the 
leaves and very dense on the stems. The pod is densely covered 
with slender bristles of varying length, instead of the coarse, 
horn-like spines peculiar to the pod of A. platyceras. In growth 
A. hispida is more compact and the flowers are on short 
peduncles seeming almost sessile. The seeds of 4. platyceras 
havea light-colored, pominent rhaphe and the coat honey-combed. 
A. hispida has the less prominent rhaphe of the same color as 
