42 PROCEEDINGS OF THE NATIONAL MUSEUM. 



THERONIA FULVESCENS FULVESCENS (Cresson). 



Pimpla fulvescens Cresson, Proc. Ent. Soc. Phila., vol. 4, 1865, p. 268, male. 



Type.— No. 1541, Acad. Nat. Sci. Phila. 

 Theronia fulvescens (Brulle) Howard, Bur. Ent. Tech. Ser. Bull. 5, U. S. Dept. 



Agr., 1897, p. 24. 

 Theronia fulvescens (Cresson) Fiske, Tech. Bull. 6, N. H. Coll. Agr. Expt. Sta., 



1903, p. 217. 

 Theronia atalantae, var. americnna Krieger, Zeitschr. Hym. Dip., vol. 6, 1906, 



p. 240, male. 

 Theronia fulvescens (Cresson) Morley, Rev. Ichn., pt. 3, 1914, p. 40. 

 Theronia atalantae fulvescens (Cresson) Viereck, Hym. Conn., 1917, p. 323. 



The difference between this and the variety mellipennis Viereck 

 has already been discussed. 



As indicated above, this species exhibits great variation. In the 

 series exaniined the females range in length from 7 mm. to 13 mm. 

 and the males from 7 to 15 mm. The color varies from almost 

 stramineous to dark ferruginous, with more or less piceous on the 

 abdomen, and the wing color from almost hyaline to deep yellow. 

 The hind femur in the larger specimens has a high, sharp, scalloped 

 ridge on the outer side of the scrobe, while in the smallest ones this 

 is almost imperceptible and entirely lacks the scalloped edge; be- 

 tween these two extremes the variation is gradual. 



The range of this species as represented in the National Museum 

 is from coast to coast and from British Columbia and New Hamp- 

 shire to New Mexico and District of Columbia. The type is from 

 Colorado, and the types of Krieger's variety are from British 

 Columbia. 



Among these specimens arc some said to have been reared from 

 such hosts as Hemerocam/pa leucostigma Smith and Abbott, Oreta 

 rosea Walker, Tortrix fumiferana Clemens, and tussock moth (Cali- 

 fornia). Fiske records it as a secondary parasite on Malacosoma 

 americana (Fabricius) through (Pimpla) Itoplectis conquisitor (Say) 

 and in one case as probably tertiary through Itoplectis and (Lim- 

 neria) Hyposoter fugitivus ( Sa}^ . He states that it is externally 

 parasitic. Fiske and Thompson ^ record it in connection with 

 Callosamia promethea Drur}^, ascribing to it both primary and sec- 

 ondary parasitic habits, in the latter case through Spilocryptus 

 extrematis (Cresson) and OpTiion macrurum (Linnaeus). All of their 

 records are based on examination of the cocoons of the host species, 

 and in eighty per cent of all cases Theronia was positively proved 

 secondary, while the statement that it was primary in the other 

 cases is based on the fact that no remains of other parasites were 

 found. To the present writer it seems impossible that a parasite 

 can be both internally and externally parasitic. Its external habit 



1 Journ. Econ. Ent., vol. 2, 1909, p. 455-450. 



