PLANT-LICE OF THE OAK. 209 



294. Drepanosiphum ? quercifoiii (Walsh). 



Larva. — Pale greenish. Incisures of the aateaute dusky. Upper surface of the 

 body, except the scufel, dusky; houey tubes long, robust, dusky at tip ; legs long, 

 with the terminal three-fourths of the femora, the extreme tips of the tibise, and the 

 tarsi obfuscated. 



Imago — Blackish ; prothorax and anterior part of the thorax sometimes varied with 

 greenish ; scutellum pale greenish ; honey tubes two-thirds as long as the femora. 

 Legs very long ; basal halfof femora pale greenish. Wings hyaline; veins brown.; third 

 discoidal vein hyaline at its origin ; stigma and subcostal veins ^ale yellowish 

 brown ; extreme tip of the front wings slightly fumose ; length of the wings scarcely 

 .2 inch. "The antenaae attain the exti'eme tips of the wings when the wings are ex- 

 panded, and the stigma is four times as long as wide and very acute at each end. 

 On oak leaves." (Thomas.) 



Although it is impossible to state positively from this description the 

 geuiis to which this species belongs, yet I think it is almost certain that 

 it should be placed in the genus to which I have assigned it. It is 

 certainly not an Aphis, in the restricted sense, and the plant it infests 

 would indicate that it is not a Siphonophora. (Thomas, Third Eeport.) 



295. Myzocallis bella (Walsh). 



" Aphis bella, — Oak leaves? Bright yellow, eyes black; antennse with the tips of 

 joints 3 to 6 black. Prothorax as long as the head, with a lateral black vitta; thorax 

 with a black vitta extending from its anterior angle to the base of the front wing. 

 Honey tubes scarcely as long as the tarsi, generally immaculate, sometimes tinged 

 with fuscous. Legs long, black except the base of the femora and the coxae. Wings 

 hyaline; front wings with the entire costa as well as its uervures black to the tip of 

 the stigmas, whence there extends a marginal dusky vitta, as wide as the costa at 

 base and middle but tapering at tip, nearly as far as the middle branch of the third 

 discoidal vein ; this vitta covers the entire length of the fourth or stigmatal vein, 

 which terminates half way between the tip of the stigma and the apex of the wing, 

 is slightly and gradually curved, and incloses a marginal cell not wider thau the 

 costa; hind wings with a costal dusky vitta extending to the tip of the wing, the 

 subcostal vein sometimes black ; remaining veins of both wings slender and pale 

 dusky, narrowly bordered with subhyaline where they traverse the terminal dusky 

 vitta of the front wing. Length to tip of wings .15 inch. 



"The antennae attain the middle of the stigma when the wings are expanded, 

 and the stigma is rather more than three times as long as wide, not very acute at 

 each end." (Walsh.) 



" The 22d of May, 1878, I discovered, at Carbondale, Ills., on the 

 leaves of the burr oak {Quercus macrocarpa), plant lice, which I am 

 inclined to believe belong to the species just described. In order tliat 

 the reader may be in possession of all the facts concerning the species, 

 I add here a description of these specimens : 



" Winged indhnduals (the only kind seen). — Rather slender, of medium size; the 

 body and all the parts except the wings a pretty creamy yellow color; the wing* thin 

 but clouded with fuscous, which is very distinct in the living insect, while the wings 

 stand erect above the abdomen ; these fuscous or cloudy spots appear to fall chiefly 

 into two irregular oblique bands, one rather in advance of, and the other behind the 

 stigma, but when a single wing is examined this arrangement will scarcely be 

 observed. Costal and subcostal veins of the front wings close together, and parallel 

 throughout ; second discoidal vein decidedly sinuate and much nearer to the third 

 5 ENT 14 



