LAWSON: KANSAS CICADELLID^. 35 



on the hind tibiae, has those parts of the leg covered with weak 

 spines or hairs quite promiscuously arranged. Here is an ap- 

 proach to the Cicadellid leg. On the other hand, it has certain 

 very distinct Membracid characters though lacking the chief 

 characteristic of the family, namely, the Membracid pronotum. 

 So similar is this insect to both these families that entomolo- 

 gists have had much trouble in deciding to which it belongs. 

 Stal placed it with the Meinhracidse, but Ashmead included it 

 with the Bythoscopidx. Van Duzee places it under a subfamily 

 of its own, as a Membracid, but as the form of that family 

 closest to the Cicadellidae. 



Thus we seem to be safe in putting the Cicadellid^ next to 

 and above the Membracid^ because of their better sensory sys- 

 tem, and because of this connecting form. It is not at all im- 

 probable, however, that the ^thalionin^ will later be placed in 

 a family by themselves, but in any case they would still consti- 

 tute the link between these two families. 



The Cercopidse do not seem to show such close, relationships 

 to the Memhracidx, nor do they seem to be as closely connected 

 with the Cicadellid^ as is this family to the tree hoppers. 

 There seem to be no forms connecting them with the leaf 

 hoppers, and yet their relationship with them and the tree 

 hoppers is veiy evident. For this reason it seems probable 

 that they are an older offshoot from this middle stem than 

 either of the other two, and this would seem to be evidenced 

 also by their peculiar life history. 



It seems probable that the nymphal habit of enveloping 

 themselves in a mass of spittle could not be a habit easily or 

 quickly developed. That it is a protective habit is certain, for 

 as Dr. F. A. Fenton has shown, while large numbers of Cica- 

 dellids and Fulgorids, also a Membracid, are parasitized by the 

 Anteoninse, we have yet to find a single instance of the para- 

 sitization of a Cercopid. Thus this habit has been long enough 

 in development to have seemingly made it an absolute success 

 in the protection of these insects from their parasitic foes. So 

 that considering their specialized life history, along with their 

 morphology and the absence of intermediate forms between 

 them and the Cicadellids, we would place the Cercojndie above 

 the latter and have them leaving the middle stem before the 

 Membracids and Cicadellids. 



