APHIS JACOBMJE. 79 



also black tarsi. Wings very long ; cubitus and 

 insertions greenisli ; stigma and veins blackish. 



Taken in company with the oviparous female and 

 at the same time. It is not an uncommon species. It 

 infests the guelder-rose, Viljurnwn opidus, forming- 

 black masses both on the upper shoots and the 

 flowers of the plant. The Aphides cause the leaves to 

 curl into various forms, and to draw themselves into 

 bunches, which are often of a red or brown colour. 



Sulzer states that the male of this species, and also 

 that of A. rumicis, is apterous. This sex, therefore, 

 appears in two forms, as is the case with A. padi, 

 A, malii and others. The cause of these double male- 

 forms is obscure, and at present we are ignorant what 

 points in the economy of these insects they satisfy. 

 The roving powers of the winged male would seem to 

 meet all requirements of impregnation. 



ArHis jACOB^^, Schr., Kalt., Walh. Plate LXII, 

 figs. 1 — 4. 



Koch, No. 2, p. 95, figs. 127, 128. 



Apterous viviparous female. 



Colom' velvet-black, greenish black, or dull greenish. 

 Figure varies from oval to globose. Under side dark 

 green. Legs, antennae, and cornicles black, but the 

 third antennal joint and the femora are obscure 

 ochreous. A well-marked spine occurs on each side of 

 the prothorax. 



Pupa. 



Smaller than the larva, but usually of the same 



