234 Annals Entomological Society of America [Vol. XI, 



of the Cicadidae persists in the Fulgoridse, the Jassid^ (Figure 7) 

 and the Membracidae, greatly reduced. In the Aphididae (Figure 

 •12) it is even deeper and in the Psyllidas (Figures 10 and lU a 

 probable trace of it remains. 



The episternum in the Jassidae (Figure 7) is subdivided into 

 three parts (aes, mes, kes) as in the Cicadidse, but in most of 

 the other Homoptera all trace of these divisions is lost. In 

 the Aphididae (Figure 12) the episternum (es) of the mesothoraT^ 

 is divided into an upper and a lower portion, the anepisternum 

 (aes) and the katepisternum (kes),* as in Cicadid^, Jassidae and 

 Neuroptera, but the median plate is not present. In the 

 Jassidae (Figure 7) a narrow band (hyp) is marked off in front of 

 the episternum and is produced into the sternum. This has 

 been shown by Crampton, 1914C, to be the hypopteron of 

 Audouin, 1820, termed the pre-episternum by vSnodgrass, IVMU). 

 As in the Cicadidae, the episternum is not separated from the 

 sternum in the Fulgoridae, Cercopidae, Jassidae, Membracidae 

 and Aphididae. The mesothoracic trochantin (tn) is readily seen 

 in all the families studied except the Psyllidae, Aphididae and 

 Aleyrodidae. 



The epimeron does not present many differences among 

 the Homoptera. The homologue of the suture dividing the 

 epimeron of Cicada into upper and lower parts, however, has 

 not been found in other families. 



Sternum. The sternum of the mesothorax is considerably 

 lengthened in all forms except the Membracidae, where both 

 mesothorax and metathorax are much condensed from front to 

 rear. The coxa of this segment in the Fulgoridae and the 

 Cercopidae bears sometimes a spur or meracanthus. 



Metathorax. Figures 6, 8, 9, 10, 11, 12 and 13.. 



Notum. The notum of the metathorax in other Homoptera 

 is usually longer than that of Cicadidae. It is often shortest 

 along the mid-dorsal line and longest as it approaches the wings. 

 In the Aphidid^ and the Psyllidae this is not generally true, the 

 median length of the notum being usually greater than the 

 length of the lateral margin. In the Jassidae the metanotum is 

 nearly as long as the mesonotum. 



'"Attention is called to an error in labelling in Figure 12. The abbreviation 

 keso should refer to that part of the plate marked pcx2 which is just anterior to 

 the pleural suture (pa). The abbreviation pcx2 would then refer to an indefinite 

 portion of this plate between keso and the posterior part of sta- 



