Biology of the Membracidae of the Cayuga Lake Basin 225 



clover. In both cases the hfe of the insect is the same. The eggs are laid 

 in the bark of stems two or three years old. The egg slits are peculiar 

 (Plate XXIV, 7), being curved and parallel and so close together that the 

 wound between them does not heal and thus considerable injury may be 

 done to the twig. Oviposition occurs most commonly in early September. 

 The process lasts about half an hour, during which time six or eight eggs 

 are laid in the slit. These eggs winter over and hatch early in May. 

 The young nymphs leave the tree on which the eggs were hatched and 

 migrate to succulent weeds, sweet clover being in this locality the favorite 

 host. About six weeks are required for complete development, each of 

 the first four instars requiring approximately a week and the last instar 

 two weeks. Ecdysis takes place on the main stem of the weed, usually 

 near the top of the plant. The process requires about ten minutes. The 

 early life of the adult is spent on the weeds and low herbs, but later the 

 females migrate to the trees for egg-laying. Marlatt (1887) records 

 the eggs of this species on weeds, but this has not been noted in the studies 

 of the local forms. The species is of considerable economic importance 

 because of the damage done to stems. Not only are the egg slits large 

 enough to cause material mechanical damage, but the puncture allows the 

 easy ingress of fungi and of other insects. 



Technical rfescrrp<ion.^ Bright green fading to yellowish in cabinet specimens; horns heavy 

 and stout, pointing directly outward; metopidium broadly convex; dorsal crest high and 

 regularly arched; posterior jirocess slender and recurved; tegmina and hind wings entirely 

 hyaline; clypeus heavy, stout, and bristled. 



Head one-third broader than long, longitudinal striate sculpturing; basal part broadly 

 curved, front sm-face yellow, not punctate nor pubescent; eyes prominent, dark brown, 

 extending beyond lateral margin of pronotum adjoining; ocelh prominent, protruding, with 

 brilliant orange borders, nearer to each other than to the eyes; clypeus strong, heavy, con- 

 tinuing lateral outhne of face, apex bristled. 



Pronotum densely and coarsely punctate; metopidium strongly convex, smooth impunctate 

 areas above the eyes, sparingly pubescent with short scattered hairs; suprahumeral horns 

 stout, blunt, projecting almost directly outward, not at all upward, tips often brownish, 

 whitish line extending backward from tip to lateral margin; lateral surface marked with 

 light-colored, semicircular impression; posterior process slender, depressed, extending halfway 

 to apices of tegmina and slightly beyond tip of abdomen, apex brow^lish. 



Tegmina hyaline, bases lightly punctate. Undersurface of body yellowish. Legs greenish. 



Length to apices of tegmina, 10 mm.; width between horns, 6 mm. 



6. Ceresa taurina Fitch (Plate xxiv, 12-15) 



183.5 Membracis taurina Harris, Cat. Ins. Mass., p. .579. 



1&35 Harris, Kept. Geol. Surv. Mass., p. 579. 



1842 Harris, Treatise, p. 178. 



1851 Enchtnopa taurina Walk., List Horn. B. M., p. 495. 



