40 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 58. 



Prepectal carina deeply curved at sternauli and usually subangulate where it 

 turns toward promesothoracic sutui-e; first tergite broader with sides divergent, 

 dorsal carinae distinct; wings at most slightly stained, stigma usually blackish; 

 face usually flat with strong furrows, rarely elevated medially and without 

 furrows Neotheronia Krieger. 



Genus THERONIA Holmgren. 



Theronia Holmgren, Ofvers. Vet.-Acad. Forh., vol. 16, 1859, p. 123. Geno- 

 type. — (Pimpla Jlavicans Fabricius) Ichneumon atalantae Poda. 



Pseudacoenites Kreichbaumer, Ent. Nachr., 1892, p. 219. Genotype. — {Pseuda. 

 coenites moravicus KTiech.ha,um.eY) = Theronia laevigata Techek, according to 

 Krieger, Zeitechr. Hym. Dip., vol. 3, 1902, p. 189-190. 



As indicated above the difference between this and the other genera 

 of the Theroniini is comparatively little and largely a matter of 

 difference in degree of development of certain features. The cari- 

 nation of the propodeum and the immaculate wings will apparently, 

 however, always distinguish Theronia from the other genera. 



In our fauna the genus is represented by but two species. These 

 are very distinct and easily identified by the characters employed in 

 the following key. Both species were originally described in the 

 genus Pimpla Gravenhorst. 



KEY TO NORTH AMERICAN SPECIES. 



Head largely yellow, more or less rufous dorsally and posteriorly; face not tubercu- 

 late; weakly punctate; first tergite in profile evenly curved above 



fulvescens (Cresson). 



Head black, face strongly punctate and medially tuberculate; first tergite elevated 

 aboA'e melmiocephalu (BruU^). 



THERONIA FULVESCENS (Cresson). 



Although a fairly common species and though originally mis- 

 placed in the genus Pim'pla, this species has apparently escaped 

 redescription, and it was not referred to its proper genus until thirty- 

 two years later, when Howard recorded the rearing of a single male 

 as a parasite of Hemerocampa leucostigma giving the author as Brull6. 

 This mistake in authorship was not Howard's but Ashmead's, for 

 the specimen on which the record is based is one of the series examined 

 and was determined by Ashmead. 



Krieger's variety americana of the European atalantae (Poda), 

 based on a specimen from British Columbia, is undoubtedly this 

 species; and a male labelled by Viereck with Kj-ieger's name is a 

 normal male of this species. In his latest mention of fulvescens 

 Viereck ^ treated it as a variety of atalantae. 



The present species is perhaps nothing more than a geographical 

 race of atalantae, but judging from a comparison of the material at 

 hand with 10 specimens of atalantae it differs in having the face 

 slightly longer, the antennae fuscous above, the discocubital vein 



1 Hym. Conn., 1917, p. 323. 



