LAWSON: KANSAS CICADELLID^:. 27 



on that species. Childs gives a list of spiders preying upon 

 the rose-leaf hopper, while Professor Osborn gives a large 

 list of spiders that have been known to feed upon leaf hoppers. 



Insects themselves furnish several predaceous enemies. 

 Thus Osborn mentions such enemies among the Nabidas and 

 Lygaeidse. Quayle mentions ladybirds, aphis lions and ants 

 as enemies of the grape-leaf hopper, while previously, Walsh, 

 Glover and Slingerland had recorded one of the dance flies, a 

 soldier bug, and the larvae of Chrysopa, respectively, as also 

 feeding on the same leaf hopper. Johnson accuses a Capsid 

 of attacking this species also. Gibson mentions the agricul- 

 tural ant as an enemy of Draeculacephcda mollipes. Childs 

 records a Scatophagid as an enemy of the rose-leaf hopper 

 and also observes that dragon flies have been observed attack- 

 ing that species. The writer one evening observed some 

 damsel flies flying over the grasses near the edge of a pond. 

 They so evidently seemed to be hunting that they were closely 

 watched and were soon seen to be attempting to catch some 

 very small Locustid nymphs and also to be after the leaf hop- 

 pers. Several times the leaf hoppers were seen to escape by 

 their characteristic shift to the under side of the grass blades. 

 Finally a damsel fly was observed to have caught one of the 

 hoppers, and we were able to get close enough to identify the 

 species as Deltocephalus inimicus and to catch the predator, 

 not, however, before the last sign of his meal had disappeared. 



There are records of at least two families of wasps that 

 provision their nests with leaf hoppers. Comstock states that 

 the Nyssonidss provision their nests with the immature stages 

 of these insects. F. X. Williams described a member of this 

 family, Harpactus gyponse, from Grant county, Kansas, which 

 used the adults and nymphs of Gypona cinerea for this pur- 

 pose. He found also that Mimesa argentifronx, a member of 

 the family Mimesidse, provisioned her nest with Euscelis 

 exitiosus. Further studies with these, and related families 

 of wasps might reveal the importance of these insects as 

 natural enemies of the leaf hoppers. 



The chief natural enemies of the leaf hoppers are the 

 parasitic insects. These are undoubtedly responsible for hold- 

 ing these insects in check, so that they do only the usual 

 amount of damage annually. Such parasites are found in the 

 dipterous genus Pipimculus and among the Strepsiptera. But 



