144 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



the mature larva having a length of about four-fifths of an inch. 

 The head is of a pale clay-yellow color, the eyes are black, and the 

 color of the body is green or yellowish green. The larva is at once 

 separated from the Dolerus larva? by the possession of but seven 

 pairs of abdominal feet." (R. and M., I.e.) When full-grown the 

 larva? enter the earth and construct silken cocoons, in which they 



FIG. 105. The grass saw-fly (Pachynematus extensicornis Norton) : a, a, eggs 

 on wheat-blade; young larvae; c, full-grown larva; d, cocoon from 

 which adult has emerged; e, f, adult insects e, male; /, female, a and 

 b, naturalsize; c-f, enlarged. (After Riley and Marlatt, U. S. D. Agr.) 



doubtless remain unchanged over winter, transforming to pupa? 

 shortly before the adults emerge the next spring. The form of the 

 adults is well shown in the illustration. " The female is stout and 

 in general light yellowish or ochraceous in color. The abdomen 

 is for the most part dark brown or black, dorsally, except the pos- 

 terior lateral margin and the extreme tip. The male is much more 

 slender and elongate than the female, and is almost black in color, 



