a 
Composilaceae . 389 
PP. Rays 20—35, never white. 
Q. Rays purple or violet, 20—30; leaves tomentose to glabrate. 
C. E. E. peregrinus Gr. 
QQ. Rays white; 30—35; leaves glabrous. W. 
E. howellii Gray 
OO. Heads numerous; annual or biennial; pappus an inner whorl of 
bristles and an outer whorl of scales. 
R. Stem with spreading hairs; leaves coarsely and sharply toothed; 
involucre bristly. E. 
E. annuus Pers. (Sweet Scabious) 
RR. Stem with appressed hairs or almost glabrous; leaves entire or 
nearly so; involucre minutely hairy. C. E. 
E. ramosus P. 8. B. (Daisy Flea-bane) 
TI. Stems either branched near the base or somewhat tufted. 
S. Blades of the basal leaves spatulate or oblanceolate or obovate. 
T. Involucre glandular or frosted-glandular. 
U. Rays 30—40. C. (E. spathulifolius.) E. leiomeris Gray 
UU. Rays 60—70. E. E. leibergii Pip. 
TT. Involucre not glandular. 
Woe hays, 20—7 >. 
W. Stems with only | head. 
X. Involucre with long white hairs. C. E, lanatus Hook. 
XX. Involucre without long white hairs altho often pubescent. 
bescent. 
Y. Basal leaves broadly obovate-spatulate; rays white. E. 
E. tener Gray 
YY. Basal leaves spatulate to linear; rays rarely white. 
Z. Basal leaves 3-veined. E. E. corymbosus Nutt. 
ZZ. Leaves |-veined. 
a. Stems branched above. W. E. 
E. decumbens Nutt. 
aa. Stems simple. U. E. confinis How. 
WwW. Stems with more than | head. 
b. Involucre white-woolly. C. (E. grandiflorus for our region.) 
Fa E. uniflorus L. (Arctic Flea-bane) 
bb. Involucre merely pubescent or hirsute, not woolly. 
c. Leaves coarsely toothed to nearly entire. W. 
Rone yA i : E. oreganus Gray 
cc. Leaves entire. 
d. Herbage conspicuously hispid-ciliate. 
e. Heads |2—-20 mm. wide; involucre-bracts acute; rays 
502-8004: E. pumilus Nutt. 
ee. Heads 20—25 mm. wide;) involucre-bracts long- 
acuminate; rays 20—50. E. E. poliospermus Gray 
dd. Herbage not hispid-ciliate, hairs short and appressed. 
f. Pappus of a single whorl of bristles. 
g. Rays 4—6 mm. long; involucre 5—6 mm. high. E. 
E. radicatus Hook. 
ge. Rays |2—20 mm. long; involucre 6—8 mm. high. 
(See aa.) 
ff. Pappus double, the outer whorl of very short bristles; 
q . rays 6—12 mm. long. E. E. caespitosus Nutt. 

VV. Rays 80—120. 

