122 THE CANADIAN ENTOMOLOGIST. 



The specimens I have vary greatly in size. The largest of them 

 measure five-twentieths of an inch in length, with an expanse of wings of 

 seven-twentieths. 



Head, black, deeply and closely indented (like a thimble) and set 

 with short white bristles. Eyes, round, prominent and set high up in the 

 head. Ocelli very small. Antennae 9-jointed (8 in the flagellum). Walsh 

 gives the proportions of the joints very accurately as 14, 3, 6, 5, 5, 4, 4, 

 4, 6. Palpi black. 



Thorax^ black, more coarsely punctured than the head. Wings hya- 

 line, veins honey-yellow. Legs, black — the hindmost and middle pairs 

 have the knees and extremities of the tarsi yellowish-white ; the first pair 

 have the tibiae and tarsi honey-yellow. 



Abdomen, in the female, large, compressed laterally, and ending in a 

 long spur turned upward ; black, smooth and polished. 



The male, which was unknown to Walsh, differs from the female in 

 these respects : — It is smaller ; the joints of the antennae, with the excep- 

 tion of the scape and the terminal joint, are more nearly equal ; the tibias 

 of the first pair of legs are considerably infuscated ; and the abdomen is 

 rounded, and diminishes regularly. Around the extremity of the abdo- 

 men are some white bristles. The head and thorax are coarsely punctate 

 as in the females, and the abdomen is polished and glabrous. 



It was too late when I obtained the galls to find the larvae of 

 E. gigantea ; but I discovered several pupee. They occupied the cells of 

 the Trypeta larvae, and were at first of a pure white waxen appearance. 

 The form of the fly was clearly outlined in them. They gradually dark- 

 ened till the flies were ready to appear. 



Concerning this species, Mr. G. C. Davis, of the Michigan Agricul- 

 tural College, writes to me, " I am quite sure the chalcid is Eu7-ytoitia 

 gigantea, although it varies slightly in colour markings. 



Pimpla inquisitor. Say. The male of P. inquisitor (P. coeiebs, Walsh, 

 Trans. St. Louis Acad., III., 141) is a very elegant insect, slim and 

 graceful. Its length is three-tenths of an inch ; expanse of wings, five- 

 tenths ; length of antenuce, two-tenths. It has a white face, in which it 

 differs from the female ; and the palpi are white. The first joint of the 

 antennae is black and much larger than the other joints, which are dark- 

 brown. The other parts of the head are black, rough and thickly set 

 with short whitish bristles, as are also the thorax and abdomen. 



The first and second pairs of legs are orange-red, with whitish tarsi. 

 The third pair have the femur orange, with black at the extremity. In 

 this pair the tibia and tarsus are beautifully banded with black and white. 



I obtained 10 males from about 50 Trypeta galls, but not one female — 

 the females, however, are not scarce in these parts. At least half the 

 galls were parasitised by the foes above described. 



