Davis: RANUNCULI OF NORTH AMERICA. 463 
papillose or spiny, borne in a head or spike; styles minute or 
elongated. 
In 1886 A. Gray wrote a revision of the North American 
Feanunculé found north of northern Mexico. This was pub- 
shed in Proc. Am. Acad. 214: 363-378. In Syn. Flora rt: 
20-39, the revision is brought down to 1895. Since that date 
the list of species has rapidly increased and since Gray’s first 
revision two new North American genera have been segregated 
from this one. In 1892 N. L. Britton discussed six species 
«¢R. repens and its Eastern North American allies,” Trans. N. 
Y. Acad. Sci. 12: 2-6. Britton and Brown’s Ill. Flora gives 
31 species in eastern United States and Canada. In 1880 J. 
Freyn gave a long treatment of about ten species in Flora, 63: 
179. 
The present treatment includes 96 species, eighteen of which 
are found only in Mexico and south of there. 
TENTATIVE Key To SPECIES AND GROUPS OF SPECIES. 
A. Sepals and petals deciduous (except in 77); petals yellow or 
white, with nectary on the claw covered by scale; sepals 5, 
(rarely only 3 or 4); petals 5 or more; carpels not utricular 
when mature, usually somewhat compressed.—Sec. EuRANUN- 
cuLus, Gray. 
B. Leaves, at least some of them, lobed or divided. 
C. Flowers yellow (except some cultivated forms of 31). 
D. Plants terrestrial. 
E. Plants not spreading by rooting branches or stolons, ex- 
cept in 12, 26 and 27. 
F. Sepals glabrous or pubescent but not densely clothed 
with black or brown wool. 
G. Akenes armed or clothed with prickles, spines or 
prominent papille......... I. arvensis; 2. muricatus ; 
3. parviflorus; 4. hebecarpus; 5. Galeottiz. 
GG. Akenes nearly smooth or pubescent. 
H. Leaves, at least some of the radical ones, divided, 
the leaflets either sessile or stalked. 
I. Radical leaves with some of the leaflets stalked. 
J. Petals short, about the length of the sepals, 
- or shorter. 
Ka lead: of frait olobose......cssciecs. 6. alceus. 
KK. Head of fruit oblong to cylindric. 
7. Pennsylvanicus. 
JJ. Petals longer than the sepals. 
