46 



the last joint, which is dusky. All the femora more or less dusky, 

 pale at each extremity ; trochanters pale, the coxte bronzed like the 

 thorax. 



Abdomen shining, impunctured, about 1.2 mm. long by .45 mm. 

 wide, oval in outline, narrowing toward either extremity ; seven dis- 

 tinctly visible segments, the first about as long as the two following, 

 second short, seventh conical. General color of the abdomen piceous 

 or bronzed black, first segment bronzed green at the extreme base 

 with a quadrate yellow patch above, which sometimes extends on 

 to the second. A similar but paler patch beneath, covers the first 

 three or four ventral segments. All the ^segments are sparsely hairy 

 upon the posterior half. 



Female.— The female is extremely similar to the male, but may be 

 distinguished at once by the abdomen and the antennse, the former 

 being more broadly ovate, more acutely pointed, and bearing a sting- 

 like ovipositor beneath, usually indeed exserted at the tip. The color 

 of the abdomen is darker, the pale area at the base being smaller, 

 less definite and of a chestnut tint. The antennae are pale through- 

 out, somewhat shorter than those of the male, with the joints less 

 hairy and more distinct. The club is pointed ovate, shorter than that 

 of the male, and not distinguishable into separate joints, so that the 

 recognizable segments in the female antennae are eleven in number 

 instead of thirteen, as in the male. The club is equal in length to 

 the two joints preceding, the tip acuminate and slightly recurved. 



LIFE HISTORY, 



Our earliest* specimens of this species were obtained June 3 from 

 Hessian fly larvae, collected on that date at Villa Eidge, in extreme 

 Southern Illinois, The earliest collection from which this parasite 

 emerged was made on the '27th May at Mt. Carmel, the adult Semio- 

 tellus appearing on the 22d of the following month. The latest ex- 

 amples of this species to appear in our breeding cages emerged 

 July 26, from flaxseeds collected on the 24th June at Anna, Illinois. 

 Further details respecting the periods of this species will be found 

 in the table at the end of this paper. 



It is worthy of note that although our breeding cages containing 

 straw and stubble infested by the Hessian fly were all reserved for 

 more than a year, no examples of this parasite occurred therein in 

 spring, although by Herrick it is reported to emerge at that time. 



Pteromalus pallipes, n. s. 

 (Plate IV. Fig. 1.) 



A short thick species with the head broader than the thorax, the 

 abdomen ovate and obtuse. Head and thorax bronzed black, 



* Although it has been heretofore supposed that the winter brood of the larva^ of the 

 Hessian fly was never parasitized. I And among our breeding cage notes an entry to the 

 effect that six living ehalcid parasites were taken on the luth May, 1883, from a cage in 

 which multitudes of Hessian flies had been bred, the wheat containing them having been 

 collected April 10, atCentralia, 111.,— a date so early that only the winter brood of larvae 

 could possibly have occurred in it. I greatly regret that, owing to a removal of my office, 

 I can not get access at this writing to the specimens on which this statement was based. 



