107 
ingalso that copulation took place only with the insect's own kind and 
not with the associated species. The two species occurred in about 
equal numbers, their habits being the same. 
Leaf-hoppers (Tettigoniidae and Jassidae). — Various species of leaf- 
hoppers of the families Tettignoiidae and Jassidae were under observa- 
tion during the past three years on experimental plats of the Depart- 
ment of Agriculture on cowpea and beans. They occurred in all 
stages, feeding on the under surface of the leaves, but were not pres- 
ent in really injurious numbers. 
The crafty leaf-hopper (Di-edrocephala versuta Say) was the most 
conspicuous species, on account of its larger size and brighter colors, 
although numerically less than the smaller Empoascas, with which it 
Fig. 26. 
b ° c 
-Diedrocephala versuta: a, male with expanded wings; b, same with wings folded; c, young 
nymph; d, last stage of nymph— all much enlarged (original). 
was sometimes associated. Adults were present from June to Sep- 
tember. This, like many other leaf-hoppers, probably lives largely 
on grasses, but cowpea is also greatly relished. Without doubt it 
agrees rather closely in habits with the better-known red-banded leaf- 
hopper {Diedrocephala coccinea-Yovst.), to which it is closely related. 
The latter, according to Messrs. Osborn and Ball, is double-brooded 
(Bui. 34, Iowa Agr. Coll. Exp. Sta., p. 615, 1897). From the latter, 
versuta differs chiefly in its smaller size and by having the vertex with 
the black markings nearly parallel with the anterior margin, which 
is usually black-lined. , There is often a pair of approximate median 
lines on the disk. D. coeeinea is reddish, with green stripes on the 
pronotum and elytra, while in versuta yellowish or greenish predomi- 
nates, with occasionally reddish on the upper surface. A mature male 
