HEMIPTERA : CLASSIFICATION. 363 



sj)ecies which subsist upon the juices of vegetables, which they 

 obtain by the assistance of their articulated proboscis, and 

 sometimes, as in the case of the aphides and sugar-cane fly 

 (Delphax sacharivora, Westw.), the mischief which they oc- 

 casion is very extensive. The forms of many of the species are 

 most extraordinary, as may be seen from the accompanying 



figures. The fe- 

 males are furnished 

 with a scaly ovipo- 

 sitor, composed of 

 three toothed saws, 

 lodged, when at 

 rest, in a bivalve 

 sheath at the tip 



a, Centrotus globularis ; 4, C. cruciatos (Brazil). , 



of the under side 



of the abdomen. With this apparatus they are enabled to 

 make an incision in the leaves or stems of plants, into which 

 they afterwards introduce their eggs. 



Latreille divides this sub-order into the three following 

 divisions : 



1. The CicadarifB, having the tarsi three-jointed, and the 

 antennae very short, terminated by a fine bristle, com- 

 prising the families Cicadidte, Fulgoridce, and Cerco- 

 pidce. 



2. The Aphidiens, having the tarsi two-joined, and the an- 

 tennae longer, without a terminal bristle, containing the 

 families Aphida and Psyllidte. Latreille also here places 

 the Thripsidce, but its organization renders this location 

 doubtful. 



3. The Gallinsecta, having the tarsi one-jointed, ter- 

 minated by a single claw. The males have two wings, 

 and are destitute of a mouth. The female is wingless, 

 and furnished with a sucker. Comprising the single 

 family Coccidce. 



