37 



tissue around the inside cavity is rather characteristic, so much as 

 to be readily recognized after a httle observation. I have found a 

 species of grass worked in by another species of an aUied insect, 

 but the manner of vvorlv is so different as to be unmistakable. 

 Isosoma elymi makes a cavity on the inside of Ehjmits canadensis that 

 is more nearly like that made by J. triticl in the wheat, but they 

 differ somewhat. 



In the fields I have found specimens of E. alhjnil emerged from 

 the pupa skin, but still inside the cavity of the stem ; others with 

 the hole by which they expected to emerge gnawed so that they 

 could almost get out, and they still there with the body protruding, 

 and others when they had gone, the clean-cut hole indicating where 

 they had obtained their freedom. I have bred many specimens 

 from the straws after they had been collected, and the conditions 

 v/ere the same as those in the field, the inside of the stems in all 

 cases being examined before putting them into the breeding jar. 



From these facts I do not see how I could avoid the conclusion 

 that Eupelmus allynii was a parasite on the two species of Isosoma." 



As no description of this important parasite has yet appeared in 

 the reports of this office, the original specihc description of Prof. 

 French, published in the Canadian Entomologist for January, 1883, 

 is here appended, accompanied by an original figure. 



Enpehvus allyni, French. 



Order Hymenoptera. Family Chalcidid.e. 

 (Plate I. Fig. G.) ■ 

 DESCRIPTION. 



Female. — Average length, .10 of an inch. Color of body and an- 

 tennae uniform black, the first with a slight greenish luster. Head 

 about .025 of an inch wide, about two thirds as long; the antenniB 

 a little enlarged at the ends, hairy ; microscopic hairs moderately 

 scattered over the head and thorax. Thorax, as well as head, 

 punctured ; wings hyaline, dotted over with microscopic hairs, the 

 thorax in its widest part about the width of the head. Abdomen 

 gradually tapering from near the base, the ovipositor slightly ex- 

 serted. 



The color of the legs vary slightly ; in five specimens the anterior 

 and posterior legs have the femur fuscous except at the ends ; the 

 tibiae with basal half fuscous, the rest yellow; the middle pair of 

 legs are yellow throughout, except the terminal tarsi. Two speci- 

 mens have all the femurs fuscous, yellow at the ends. One speci- 

 men has all the femurs pale red, and the tibite fuscous, but this is 

 probably a change from yellow by the poison bottle used in killing. 

 One is marked like the first five, with the yellow replaced by pale 

 red; another is like the first five,*except that the middle tibise are 

 a little clouded at base. 



Male. — In this sex the body, wings and antennas are colored like 

 the females, but the antennae are a little more slender at their ends. 

 The head and thorax have about the same measurements, but the 



