ISO Journal New York Entomological Society. [Voi. xix. 



club : the latter conical, ending in a spur, the basal joint large, ovate, nearly 

 as long as funicle joint 3, the apical' joint a fifth or sixth smaller. Ring-joint 

 narrow and short. Pubescence whitish hairs of moderate length arranged in 

 whorls and arising from tuberculate white spots. Mandibles 2-dentate, the 

 teeth about equal. 



From many specimen.s, 2/3-inch objective, i-inch optic, Bausch and 

 Lonib. 



Male.- — Length, 1.95 mm. 



The same but more metallic blue especially at the legs and dorsal aspect 

 of the second abdominal segment. Abdomen not stout and conic-ovate but 

 depressed, oval and truncate distad, the genitalia exserted. Antennae the 

 same but the peduncles of the funicle joints are more conspicuous. 



From three specimens, the same magnification. Described from 

 the following series of specimens received from Mr. Warren Wil- 

 liamson, a graduate student in Entomology at the University of Illi- 

 nois and for whom the species is named. The whole number was 

 reared from Conopid puparia taken from BoJiibus cuncricanonim 

 Fabricius. 



(i) Labelled "10 — 10 — 20/Exp. i. Conopid on Bombns amcri- 

 canontm Fabricius, Urbana, 111., Oct. 20, 1910. Mcstocharis emerged 

 May 20, 191 1. W. W. seven females, one male emerged; twenty- 

 eight females found in a compact mass, interiorly, besides five pup?e 

 and three larvse (dead). The host puparium had been broken before 

 emergence."' (2) Labelled '" 10 — 10 — 9/Exp. i. Conopkl on B. amcri- 

 caiidriDii. Same. The host puparium contained dead pupae only of 

 the parasite ; these were in a mass, each pupa upon a single, large, 

 pyriform meconium which resembled chocolate jelly. A second Con- 

 opid puparium bearing the same label was also present; on May 27, 

 191 1. 39 females of the parasite emerged, all from a single, round 

 hole in the cephalo-lateral aspect. Inside this host puparium, after- 

 ward, was found a wet mass of " viscera " in which was embedded a 

 dead adult female parasite and a larva, besides a number of pupal 

 casts." (3) Labelled "10 — 10 — 9/Exp. i. The same; emerged May 

 26, 191 1. Fifty-one females, three males from two small round holes 

 at the caudo-dorsal and lateral aspects. The host when opened was 

 hollow, containing mere membranous fragments of the host, un- 

 recognizable, and five dead female parasites and a mass of cast pupal 

 skins among which were a few nieconial pellets." 



Habitat. — Illinois (Urbana). 



