CHARLES W. HOOKER. 121 



by T. viorio. One cocoon of T. morio, however, produced a 

 large number of minute Hymenoptera, secondary parasites, 

 which Dr. Ashmead determined as a new species of chalcid 

 and has described* as Encyrtus thyreodontis. The exact range 

 and effectiveness of this hyperparasite are unknown, but "from 

 this one cocoon 170 specimens were preserved and many 

 lost. ' ' The larvae of T. morio are occasionally at least attacked 

 by fungi, for Mrs. A. K. Dimmock states that "one of the 

 larvas taken at Canobie Lake, N. H., after coming out of its 

 host died of fungus of apparently the same species which 

 attacks its host larva." 



In numerous rearings of two related sphingids, Smerinthus 

 jamaicensis Dr. {S. geminaius Say) and Paonias myops, no 

 parasitism by T. morio was observed. 



The U. S. National Museum collection contains specimens 

 of this species from Nyack and Long Island, N. Y. ; Mass. ; 

 Conn. ; Washington, D. C. ; Mo., and Kansas. 



Tliyreodon feri'ugiueus n. sp. 



Head flavo-ferruginous ; thorax and first abdominal segment ferrugiji- 

 ojis, the rest of the abdomen shining black ; wings black, with a slighj 

 purplish reflection except at the apical fnargin. 



Length, 40 mm. ; wing, 22 mm. ; spread, 47 mm. 



Head ferruginous, more or less tinged with flavous ; antennae with 

 scape ferruginous (remainder missing); ocelli small, distant from the 

 tops of the eyes ; eyes medium sized, at a little distance from the base 

 of the mandibles, emarginate ; face between the eyes and bases of the 

 antennae mostly flavous ; clypeus pointed in front ; clypeal foveae shal- 

 low, more or less elongate ; mandibles stout, bidentate, tipped with 

 black. 



Thorax and legs ferruginous, dorsum of thorax and the posterior 

 legs darker; mesonotum with parapsidal furrows distinct, crenulated, 

 converging and uniting at or before the posterior margin. 



Pleurae and pectus smooth and shining ; metathorax with sides smooth 

 and shining, behind finely rugose, its posterior two-thirds with a wide 

 median furrow in which is an indistinct median carina ; the outer 

 border of the metathorax — behind — slightly raised, forming a depres- 

 sion between the median furrow and this elevation. 



Wings black with a purplish reflection, except at the apex ; stigma 

 lacking ; nervulus interstitial ; nervellus broken above the middle ; 



* Proceedings of the Entomological Society of Washington, Vol. IV, 

 page 156, No. 7, 9 . 



TRANS. AM. ENT. SOC. , XXXVIIl . (16) 



