420 
Journal of Agricultural Research 
Vol. XXVI, No. 9 
of E. tricincta, notably tricincta Fitch and calycula McAtee, show exactly 
the opposite habit, occurring rather commonly on wild Vitis vulpina , 
Clinton, and other thin-leaved cultivated grapes, but being practically ab¬ 
sent from varieties such as Concord and Catawba. Varieties tricincta and 
calycula , in both of which the anterior cross-band overlaps the base of 
the scutellum, intergrade; are very much more widely distributed 
geographically than cymbium , with known range including Connecticut, 
Tennessee, and Kansas; and occur in much smaller numbers than 
cymbium. This ecological difference between cymbium and tricincta - 
calycula explains the apparent contradiction between our results and 
those reported by Hartzell (3, p. J5“jd) 2 in 1912. 
THE THREE-BANDED GRAPE LEAFHOPPER 
This discussion will be restricted to a single form, Erythroneura tricincta 
var. cymbium , because of its great economic importance. Although the 
common name “ three-banded grape leafhopper” is applicable to several 
other forms of tricincta of less economic importance, it is here adopted 
for this insect, being the name applied to it by grape growers throughout 
its range. The term “three-banded” is used by Fitch (2, p. 63) in the 
original description of E. tricincta. (E. tricincta var. tricincta is doubtless 
the typical variety of Fitch.) 
ECONOMIC IMPORTANCE 
Though not especially abundant in 1919, Erythroneura tricincta var. 
cymbium caused severe injury in 1920 and was about as numerous and 
destructive in 1921 and 1922. In numerous localities on the Lake Erie 
Islands and in the Sandusky region in 1922 the crop loss in Catawba 
vineyards was unusually heavy, as a large part of the fruit on injured 
vines failed to ripen properly. Well ripened Catawba grapes of good 
quality brought prices ranging from $100 to $140 per ton, while “ pale ” or 
poorly ripened grapes sold as low as $40 per ton. 
distribution 
While common along the southern shore of Lake Erie west of Cleveland, 
Ohio, the form cymbium is infrequent to the east, not extending more 
than 10 miles east of Cleveland. It is most abundant in the Sandusky 
region and in the southwestern Michigan grape belt. Our own collecting 
does not extend west of Benton Harbor, Mich., where it is very abundant 
and injurious, nor north of Grand Rapids, Mich., where this form is less 
abundant than Erythroneura comes. In Ohio, the form apparently does 
not extend as far south as Columbus, although just where it stops to 
the southward has not been determined. 
A critical survey of the literature of this variety, judging from 
descriptions included in general reports on leafhoppers, shows it doubt¬ 
fully present in Kansas (Lawson, 5). McAtee (6, p. 310) records it 
from Michigan, from Dallas, Tex., and from Northeast, Pa. The last 
record, however, represents material originally secured in Ohio and used 
by Johnson (4, p. 10-11) in 1912 for life-history studies. As no specimens 
of cymbium could be found in the vineyards nearest Johnson’s old insectary 
in 1922, the form apparently did not establish itself in the region. The 
personal collections of Prof. D. M. DeLong at Ohio State University 
contain specimens of cymbium taken at Clarksville, Tenn. W. A. Ross 
1 Reference is made by number (italic) to “Literature cited,” p. 434. 
