, APHID JE. 



523 



swellings on twigs like pine and spruce cones. The antennse 

 are short, five-jointed and slender ; there are three straight 

 veinlets arising from the main subcostal vein and directed out- 

 wards, and there are no honey tubes ; otherwise these insects 

 closely resemble the Aphides. A species (Fig. 520 ; a, pupa 

 seen from beneath) closely related to the European Adelges 

 (Chermes) cocdneus of Eatzburg, and the A. strobilobius of, 

 Kaltenbach, which have similar habits, we have found in abun- 

 dance on the spruce in Maine, where it produces swellings at 

 the end of the twigs, 

 resembling in size 

 and form the cones 

 of the same tree. 



Under the name 

 ot Hamamelistes Dr. 

 Shimer describes a 

 species, H. cornu « ^jg- 520. 



(Fig. 521, wings), which inhabits "obliquely conical or horn- 

 like galls on the upper side of the leaf of Hamamelis Virgin- 

 ica, the Witch Hazel, opening on the under side of the leaf." 

 ■In this genus the "wings are laid flat on the back in repose, 

 extending much beyond the body," while the honey tubes are 

 either small or obsolete, and the antennse are short, being from 

 three to five-jointed. 



The genus Thelaxes differs in the wings being folded flat 

 on the back, and there are but two veins in the hind wings, 

 one subcostal, the other median. Thelaxes ulmicola "Walsh 

 inhabits galls on the leaves of the elm. Mr. 

 Walsh states that the winged females are black 

 and more or less pruinose. In Byrsocryx)ta the 

 wings are steeply roofed, according to Walsh, 

 and in the six-jointed antenna "the sixth 

 joint is nearly as long as the fourth and fifth together." This 

 genus also consists of several gall-inhabiting species. In the 

 species of Pemphigus^ which produce gall-like excresences on 

 plants, the fourth to the sixth antennal joints are nearly equal 

 in length, and, as in Byrsocrypta, there are two median veins, 

 the third vein of the wing being simple, while in Eriosoma it is 

 forked. Mr. Walsh has "ascertained from repeated observa-. 



