46 BRITISH APHIDES. 



Both larva3 and pupee are plentifully powdered witli 

 very fine white, mealy, fibrous particles. 



Winged viviparous female. 



Inch. Millimetres. 



Expanse of wings 0*300 7"62. 



Size of body O-OSOxO'OSO 2'02x0-76. 



Length of antennse 0"060 1"54. 



cornicles O'OIO 0-25. 



Head, thorax, and antennse, black. Abdomen green, 

 with four lateral dots on each side. Legs ochreous or 

 dingy yellow, with black knees and tarsi. Rostrum 

 reaches to the second coxae; yellow, with a brown 

 point. Cornicles rather short, black or dark olive. 

 Some specimens have darker interrupted bands on the 

 abdomen, and a dark patch above the cornicles. 



Wings long, much longer than those of Aphis 

 cratcegi, with which Aphis mall has sometimes been 

 confounded. Cubital vein with its second furca very 

 near to the wing-margin. Insertions and stigmata 

 pale green. 



Common on the leaves of the garden apple and the 

 wild crab, Pijrus mains. According to Kaltenbach, also 

 on the pear, and the whitethorn, Gratoigus oxycantha. 



The apterous forms are most plentiful in May and 

 June. The winged insects abound most in July, when 

 they spread their colonies so much, that sometimes the 

 vast orchards of Devonshire are wholly robbed of their 

 fruit through the shrivelling of the leaves. The bark 

 of the trees sometimes is blackened by the glutinous 

 secretions voided by these Aphides. Often, however, a 

 crop is saved by the timely appearance of lady -birds 

 (Coccinella), a single individual of which has been seen 

 to suck dry upwards of one hundred Aphides in an hour. 



Soon after the multiplication by parthenogenesis 

 had been proved in this family of insects an opinion 

 seems to have been entertained by many that the pro- 

 cess of a-sexual viviparism could be prolonged for an 

 indefinite time, and an extreme idea arose, that there 



