442 INSECTS INJURIOUS TO VEGETATION. 



itself, the whole substance of which became enlarged and 

 distorted. In a smaller number of cases, it was found to 

 occupy the culm or stem, above the joint, which was swollen 

 so as to form an irregular gall-like tumor, while the leaf-sheath 

 remained unaffected. These woody tumors had several little 

 cells in them, varying in number from six to ten or more; and 

 every cell contained an insect, in the pupa or chrysalis state. 

 The samples of straw reserved for myself were put into a 

 small glass jar to secure the insects when they had completed 

 their transformations. Early in May, winged insects began 

 to perforate the tumors and come forth, and they continued to 

 issue during ten days or more. Their appearance was probably 

 hastened by the jar being kept in the house instead of being 

 exposed to the air abroad. These insects so nearly resemble 

 in form, size, and color, the Eurjjtoma formerly obtained from 

 the barley-straw, that I am persuaded they are, at least, mere 

 varieties of the same species, if not absolutely identical. The 

 only apparent difference between them consists in the color of 

 the fore shanks; these, in the wheat-insects, being pale yellow, 

 and faintly tinged with black only on the outer edges, in a 

 few individuals. Among fifteen specimens only one male was 

 found, and this did not appear till the month of June. Dr. 

 Fitch obtained from his samples of straw above one hundred 

 specimens of the same kind of Euri/tomai and all of them 

 females. Among them he found another Chalcidian insect, a 

 species of Pteromalus, probably a parasite of the Eurijtoma^ 

 and has favored me with a description of it. The head and 

 thorax are of a dark metallic green color; the abdomen is 

 slightly depressed, polished, purplish black above, bright cop- 

 per-colored beneath. The antennas are black, except the basal 

 joint, which is of a brilliant copper-color. The thighs are pale 

 yellow; the shanks and feet blackish, the hind pair with a 

 broad pale ring around the bottom of the shank and the con- 

 tiguous part of the foot. The length of the body is ten 

 hundredths of an inch, being somewhat less than that of the 

 Eurytoma. From my samples of the straw I have obtained 

 another and a different parasite, belonging to the same family, 

 but to the genus Torymus. The specimen is a female, and, 



