84 THE APHIDES OF GUERNSEY. 



mits of which are expanded into sucking discs or pulvilli. 

 When placed on a slip of glass under a low magnifying ])0wer 

 it moves, but with extreme deliberation. Its progression is 

 ludicrous, poising itself on its hind legs and employing its 

 pulvilli to secure its position before it attempts to make any 

 further advance. Its habits are quite solitary, strongly fixing 

 itself to the inner angles of the leaf ribs of the sycamore or 

 maple. 



The ApJiidcE are divided into five tribes or families. 

 Four of these may be distinguished from each other by a 

 difference in the veining of the wings, and the fifth is wing- 

 less. 



The first tribe (the Aphidince) contains by far the 

 largest number of species, as the Rose, Turnip, Bean, Pea and 

 Hop Aphides. 



The second tribe (the Schizoueurince) includes only seven 

 British species, of which Scliizoneura lanigera is the best 

 known. 



Of the third tribe (the Pemphifjince) the lettuce root 

 Aphis, Pcmpliigus lactucarius is a good example. 



The fourth tribe (the CJiermesince) contains the pine apple 

 gall Aphis of the Spruce Fir, Chcrmes ahietis^ and the 

 PhyUoxera of the Vine. 



The fifth tribe (the Rhyzohiind) is wingless and found 

 chiefly at the roots of grass or corn. 



The life history of the AphidincR is briefly described as 

 follows in Miss Omerod's valuable little work, '' Guide to 

 Methods of Insect Life : " " The wingless females, which are 

 produced very soon after the males in autumn, lay eggs ; 

 sometimes singly, sometimes in clusters. From these eggs 

 in the following spring (or possibly before), young Aphides 

 hatch, which are all females : they go quickly through their 

 changes up to the perfect state, and then they produce 

 living young, still all females, some of which are winged, 

 some wingless, go on until, in autumn, the last generation 

 occurs, which is of males as well as females ; and the females 

 of this, as we said before, instead of producing living young, 

 produce eggs, which start the next year's attack. 



" This is a general sketch of the history of the great tribe 

 of Aphidince. This tribe includes the Corn Aphis ; the Green 

 Dolphin, as it is called, of the peas ; the Collier of the Beans ; 

 the Hop Aphis, which in 1882 caused a loss of more than 

 a million and a half pounds sterling to this country ; the 

 Turnip and Cabbage Aphides ; the Black Cherry Aphis, and 

 many other kinds too numerous to name at present. 



