﻿14 PROCEEDINGS OF THE NATIONAL MUSEUM vol. loo 



apically; there are six strong hairs around the rounded posterior 

 angles of the pro thorax, but none across the median posterior margin, 

 except one slender hair on each side of the median notch. The frons 

 is not evenly circular as in cimicodes, but slightly pointed medially, 

 and with a noticeable swelling at each side (see fig.)- 



The pro thorax is proportionately much narrower and longer; the 

 prosternal plate is very differently shaped (according to figure by 

 Ewing) and is set with numerous short, peglike spines, thicker in 

 anterior portion (see fig.). 



The chaetotaxy of the abdomen seems to be different from E. cimi- 

 codes, according to the description by Ewing (Proc. U. S. Nat. Mus., vol. 

 77,art.20,p. 11,1930). He says:" Dorsal setae rather short and hairlike, 

 pleural tufts pronounced . . . Ventral abdominal setae swollen at 

 their bases and tapering to an exceedingly fine point." In the present 

 species a series of medium-sized hairs occur on the posterior margins 

 of the tergites, about as long as the width of the succeeding segment 

 but alternated with a short, slender spine. At the posterior angles of 

 the narrow pleurites I to VII are two heavy spines, not mentioned in 

 any description of cimicodes. The setae along the posterior margin of 

 the sternites are quite contrary to the description by Ewing, con- 

 sisting of only short, slender hairs of uniform length and having no 

 "setae swollen at their bases and tapering to an exceedingly fine 

 point." Perhaps one of the most striking differences between cimi- 

 codes and the new species is the absence of spines along the margins of 

 the tibiae, there being merely a few slender hairs on outer apical 

 portion. Denny's enlarged figure of the legs of cimicodes, showing 

 detailed chaetotaxy, is very different from the species here described, 

 and there is no reason to assume that his figures are not correct. 



The male genitalia are simple, with a short, slender basal plate, 

 widening at the base and bearing long, slender, almost straight 

 parameres. 



The description given by Ewing was made from a specimen taken 

 on Chaetura jpelagica at Columbus, Ohio, and he is correct in saying 

 that there may be some doubt that this specimen is the same species 

 as those taken on the European swift {Ajpus ajpus). My belief is 

 that this specimen from Chaetura pelagica will prove to be distinct 

 from E. cimicodes when direct comparison can be made with European 

 material from the type host. Also, Ewing's description was made 

 from a female, while the type and single paratype of pacificum are 

 both males. I doubt, however, if there will prove to be many, if 

 any, differences between the sexes in the characters here used to 

 differentiate the new form. In addition to the type another adult 

 male was taken on the same host species on January 29, 1945, by Mr. 

 Baker, and both specimens are identical. 



