THE CLOVER LEAEHOPPEK. 105 
Distribution is general from New England through southern 
Canada, Washington, and Oregon and south to Georgia, Mississippi, 
and Vera Cruz, Mexico, and west to Arizona and California. 
It affects a wide range of crops, as might be inferred from mention 
already made, but it shows a preference apparently for clover, alfalfa, 
and other legumes and so far the nymphal stages have been taken 
almost exclusively on plants of this group. During the season of 
1909 it was observed in stubble with grass and clover at Grand Forks, 
N. Dak. July 28. It was found at difTerent points in Ohio in August 
and September — at Cedar Point during August; at Wooster during 
September, in stubble-fields, including clover. At Lafa} r ette, Ind., on 
October 5, it was found on alfalfa; at Harrisburg, Pa., November 5; 
at Reading, Pa., on November 6, in pasture and in wheat; at College 
Park, Md., on November 11, in grass strip next to wheat; at Arling- 
ton, Va., on November 12, in wheat plat; at Washington, D. C, on 
November 13, in leaves ( ?); at Raleigh, N. C, on November 15; at 
Columbia, S. C, on November 16, in wheat; at Knoxville, Tenn., on 
November 22, on alfalfa and red clover; at Ma} T sville, Ky., on De- 
cember 4, in wheat, near border of field. While not in excessive 
numbers in any of these localities it was often abundant enough to 
be considered as a distinct drain on the crop. In every case where 
it was observed in wheat fields it was in the adult stage and had very 
certainly migrated thither from adjacent pastures and meadows. 
Probably in none of these was clover entirely wanting, and I believe 
we may safely base measures for avoiding injury to wheat or other 
fall-planted crops on the assumption that it comes from near-by 
meadows or pastures that have been a year or two at least in grass 
and clover. As for the injury in clover fields or alfalfa, I believe this 
to be very considerable not only in checked growth but very prob- 
ably in lessened seed production from its attacks on the blossoms 
and newly forming seed. Herbert T. Osborn, of the Bureau of En- 
tomology, reported it as abundant and apparently the most injurious 
jassid in alfalfa at Wellington, Kans., in the winter and spring of 1910. 
This species is closely related to the Agallia venosa Fall., of Europe, 
which, according to Edwards, is "very common at the roots of grass, 
etc." This would indicate a similarity of habit and possible deriva- 
tion from a common ancestral form. 
The adaptation in our species to clover and alfalfa, which are both 
introduced plants, may therefore have been an easy matter since it 
probably fed upon some native legume before these plants were avail- 
able. The increasing abundance of the species on adaptation to a 
new food plant simply follows a very general law with reference to 
the adaptation of native insects to introduced crops. Considering the 
present distribution of the species, and especially in its relation to 
other species of the genus, it seems probable that it has migrated from 
