20 BOTANICAL GAZETTE | JANUARY 
gland of the involucre 
is replaced by a tri- 
lobe. The involucre 
is more subcylindrical 
than turbinate. Seed 
cate laterally, elon- 
gated-tetragonal, 
1.4™™ long, 0.579 
broad, the ventral fac- 
ets concave, crossed 
by several prominent regular ruge; the dorsal facets plane, 
densely covered by prominent irregularly anastomosing ruge. 
Dr. Palmer’s 43 Durango specimens agree with the type, and 
are counterparts of Pringle’s 80 Jimulco Valley, and 1076 plains 
of Chihuahua. 
EUPHORBIA SERPYLLIFOLIA Pers. Ench. Bot. 2:14. 
This species is readily distinguishable by its truncate-serrate 
leaves. The fifth gland of the 
involucre is represented by a 
truncate sulcus between two 
enlarged involucral lobes. Seeds 
ashen or amber-color, 1.1™™ 
long, 0.6™" broad, strongly tet- 
ragonal; the facets of the ven- 
tral surface concave, marked by 
a few indistinct rugz; those of 
the dorsal surface convex, rugee 
anastomosing, and somewhat 
more evident. 
In Dr. Palmer’s 899 Duran- 
go the involucres are externally 
hairy, otherwise —though robust in habit—his specimens agree 
with the type, and with E. L. Greene’s Bear creek (Colorado) 
and M. E. Jones’ 3998 Flagstaff (Arizona). 
angular-linear sixth 
ashen, somewhat fal- E : 
al lik Se, 
