162 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



A MUCH DESCRIBED ICHNEUMONID AND ITS SYSTEMATIC 



POSITION. 



BY R. A. CUSHMAN, 

 Bureau of Entomology. 1 



The difficulties of the student of the Ichneumonidae are well 

 demonstrated by the vicissitudes through which the species dis- 

 cussed below has passed. 



In 1868 Cresson described, from the male only, his Meso- 

 leptus (?) muliebris. 



In 1875 Provancher described, from the female, Mesoslenus 

 rufipes, which, in 1879, he transferred to the genus Mesoleptus. 



In 1880 Provancher described, from the female, Echthrus 

 pediculaius, and, in 1886, Mesostenus pleuricinctus, also from the 

 female. 



In 1894, Davis, who had examined a large number of the Pro- 

 vancher types, synonymized Mesoleptus rufipes Provancher and 

 Echthrus pediculatus Provancher, which latter he doubtfully 

 referred to the genus Eux'orides Cresson. 



In 1895, Davis, after having examined more of the Provancher 

 types, added Mesostenus pleuricinctus Provancher to the above 

 synonymy, and stated that "they are all, with very little doubt, 

 synonyms of Cresson's Mesoleptus (?) muliebris, which is the male." 

 In this paper Davis, considering the species more likely cryptine 

 than tryphonine or pimpline, referred it, because of the Junulae, 

 to the tribe Phaeogenini, evidently considered by him cryptine 

 rather than ichneumonine, and placed it in Foerster's genus 

 Diacr-itus, thereby making it the genotype of Diacritus Foerster. 



Dalla Torre adopted Davis' synonymy and generic conclusions, 

 and Viereck gives as the genotype of Diacritus, Mesostenus rufipes 

 Provancher. 



Since the publication of Davis' synonymy this species has been 

 again described, this time by Viereck under the name Fleet ivcidea 

 (Aperileptusl) contentionis. 



In 1875 Provancher described from the male his Mexoh'/itn* 

 variabilis, which he later (1879) synonymized with muliebris 

 Cresson. But, as will be shown later, this synonymy is incorrect. 



Mr. S. A. Rohwer has recently examined the Provancher types, 

 and there is in the National Museum a specimen of this species 

 which is a Rohwer homotype of all of Provancher's species except, 

 of course, variabilis. At the time he examined the types Mr. 

 Rohwer was of the opinion that variabilis Provancher can not be 

 the male of the present species, but that it is a mesoleptine. In 



1 Published by permission of the Secretary of Agriculture. 



