10 BRITISH APHIDES. 



Abdomen greenish, with a double row of dorsal spots. 

 Antennae and legs rather long. 



Taken in copula with the following. 



Ociparous female. 



Oval, wholly dingy green, with brownish stains and 

 streaks passing behind the eyes and over the thorax. 

 Abdomen with four rows of brown spots, and seven 

 smaller dots on each side, marking the sites of certain 

 pores other than the stomata, which last are placed on 

 the inferior surface of the body. Legs and antenna 

 short. The abdominal cavity of the specimen described 

 was almost entirely occupied by two large yellow eggs, 

 the safe delivery of which is a mechanical marvel. 



The prevalence of Thelaxes in England is variable 

 both as to quantity and locality. Some years it is 

 very abundant, whilst in other years it is difficult to 

 find. In the late spring of 1871 many twigs and young 

 shoots of Qucrcus sessilij!<>r<i growing round Haslemere 

 were infested by many thousands of larvse crowded 

 round the queen-mother. For several years afterwards 

 I failed to discover any trace of the species on these 

 oaks. In June, 1881, Mr. Foran kindly furnished me 

 with examples taken on Quercus robur near Eastbourne. 

 They were sparsely scattered over the flowers of this 

 oak. The winged form, he told me, was infrequent, 

 but the large queen-Aphides continued throughout 

 July adding to the population of their respective colo- 

 nics. The species is not uncommon in Epping 

 Forest, and at Southgate. 



The wings of the parthenogenetio females are often 

 of a rich violet, with a metallic sheen. 



The venation is subject to remarkable variations, 



