88 BEITISH APHIDES. 



Prof. Riley * states that in Phylloxera the embryos 

 of the sexed insects remain quiescent in their 

 sacs for a fortnight before they emerge from their 

 dehcate pelHcles. This would imitate to a certain 

 extent a hatching, but the phenomena are certainly 

 distinct. 



The gall-making Aphides are better represented on 

 the Continent of Europe than in Grreat Britain. Pas- 

 serini described twenty Italian species, including 

 Tetraneuva and Aploneura. Derbes wrote on five 

 species inhabiting Pistachia terebintlius, none of which 

 are British. Lichtenstein has added others. With 

 reference to conformation, Derbes remarks that in the 

 terebinthine Pemphiginw the ocellus or supplementary 

 eye occurs only in the winged forms. Some apterous 

 females are wholly blind, for, like cave-inhabiting 

 reptiles and beetles, they are cut off from light in their 

 closed habitations, and eyes would be useless. Derbes, 

 however, says the ocelli are to be found in the first 

 generation of others, and that these are their sole 

 organs of vision. f 



A question may be raised whether these organs, 

 containing, it is true, only five or six facets, are really 

 referable to ocelli. 



Genus XXV.— SCHIZONEURA, Hartig. 



Rostrum moderately long in the adult, much longer 

 in the young. 



Antennge with six articulations omitting the terminal 

 unciform process. The first and second joints very 

 short, the third much the longest, and in all cases either 

 ringed or cupped ; the fourth g,nd fifth about equal, 

 and also usually ringed ; the sixth joint rather shorter 



* Vide seventli * Ann. Report of State Entomologist,' pp. 91, 92, 

 note. 

 t Derbes, ' Ann. des. Sc. Nat.,' 1869, p. 96. 



