CONTRIBUTIONS FROM THE GRAY HERBARIUM OF 
HARVARD UNIVERSITY.— NEW SERIES, No. XLI. 
By Sipney F. Buake. 
Presented by B. L. Robinson 14 May, 1913. Received 12 June, 1913. 
I. A REDISPOSITION OF THE SPECIES HERETOFORE 
REFERRED TO LEPTOSYNE. 
Among the numerous genera of the Helianthoid Compositae scarcely 
any has had a more involved history than the genus Coreopsis L., 
its synonymy embracing more than a score of generic names. On the 
one hand closely allied to the still larger genus Bidens, and perhaps 
not clearly separable from it, it is related on the other to various smaller 
and much more distinct genera. One group of about a dozen species, 
characterized by fertile rays and the presence of an annulus on the 
tube of the disk-flowers, has by many authors been kept distinct under 
the name Leptosyne DC., but by Bentham and Hooker,! Hoffmann,? 
and more recently by Hall,* has been reduced to Coreopsis, apparently 
with justice. In habit, involucre, and achenes its members are closely 
similar to various species of genuine Coreopsis; and while most of the 
species have a thickened hairy oy at base of throat in the disk- 
corollas, this is glabrous in some species * and entirely absent in others,® 
while the rays although usually fertile are sometimes sterile or neutral 
in the section Pugiopappus; so that in the absence of any quite con- 
stant diagnostic character and because of the general very close simi- 
larity, it seems advisable to follow the authorities above mentioned 
in referring the genus definitely to Coreopsis. 
The genus Coreocarpus Bentham, on the other hand, although made 
a section of Leptosyne by Gray and included by Hoffmann in his section 
Leptosyne of Coreopsis, departs in its isomorphic involucral scales so 
. Pl. ii. 8385 (1873). 
Engler & Prantl, Nat. Pfl. iv. Ab. 5. 243 (1890). 
3 Univ. Calif. Pub. Bot. ili. 189 (1907). 
maritima, L. gigan 
; L mexicana, L. insularis; and Electra has no annulus. 
