306 



The worst discomfort experienced during 191 5 at White Heath 

 was that provided by "chiggers" (Tronibidiuin sp.), which were in 

 abundance — an unusual occurrence in this part of the state. 



As the collection of CJiironomidcc was but an incident in a rather 

 overcrowded program, I found it impossible to do any work on the 

 early stages of the aquatic forms, and the additional data obtained 

 refer only to the habits of the imagines and to certain species which 

 are either new to science or are not included in my previous paper. 



Notes on Blood-sucking Ceratopogonin.^ 



In my previous paper I listed as blood-sucking species, Ciilicoidcs 

 varipennis, C. sangiiisugus, C. hccinatopotus, and C. guttipennis, the 

 first two biting both man and cattle, the third biting man. and the last 

 biting a horse. Before listing my records for this year it may be of 

 interest to mention those given by Pratt in 1907 for this group*. 



He lists six species as blood-sucking, viz., Ccratopogon guttipennis, 

 C. sangitisiiga, C. stellifer, C. varipennis, C. einctus, and C. nnicolor. 

 All of these species were described by Coquillett, who placed them in 

 the genus Ceratopogon (sens. lat.). All but nnicolor belong to Culi- 

 coides. The generic position of nnicolor is uncertain. It will be seen 

 from a comparison of the two lists that four species recorded by Pratt 

 are also in the Illinois list. This year, I have been able to find several 

 additional biting species. 



CuLicoiDES GUTTIPENNIS Coquillettf 



In 191 4 I did not succeed in obtaining specimens of this species 

 attacking man, although well aware that it was considered as one of 

 the most persistent biters in the genus. This year, however, upon dif- 

 ferent dates, I have obtained a large number of specimens in the act of 

 biting. I found that by exposing the bare arm and settling quietly down 

 by the side of the river I could readily obtain any number of specimens 

 of this species. The exposed part, however, was not most subject to 

 attack, as the insects appeared to settle much more readily upon the 

 clothes, especially upon the legs, and almost invariably made their way 

 up between the legs, or, when one was in a sitting posture, directed 

 their efforts towards the under surface and particularly at the back of 

 the knee if the leg were drawn up. It is obvious, of course, that in 



*"Notes on 'Pimkies'," Some Miscellaneous Eesiilts of the AVork of the Bureau 

 of Entomology— IX, Bull. 64, Part III, Bur. Ent., U. S. Dept. Agr. pp. 23-28. 



tCitation to original publication is given only when species is not included in my 

 previous paper. 



