242 



INSia'TS IXILKIurS TO NlXiKTAP.LES 



comparison of the illustration of each. According to Marlatt, 

 deposition of the eggs is on the under surface of the leaf, and 

 by reference to figure 158, a, it will be seen that eggs are 

 placed usually in parallel rows bordering the larger veins of 



Fig. 158.— Larger sweet-potato sawfly. 0, Female sawfly 3 antenna of male; 6 young 

 larva: c, section of infested sweet-potato leaf, showing egg deposit' d same showing larva 

 hatching and feeding, a, b, d, S , Enlarged: c. natural size. (Adapted from Marlatt.) 



the leaf. Larwe are seen hatching from the pouch-like egg 

 receptacles or blisters at b. 



Remedies. — Both these sawfly larvte when abundant may be 

 easily controlled by the prompt application of hellebore or 

 arsenicals when they make their first appearance. 



Cutworms. — Since sweet potato is cultivated in seed-beds, 

 it is subject to the ravages of cutworms when set out in newly- 

 plowed fields. One of these, the dark-sided cutworm (Car- 

 ncades messoria Harr.), appears to be particularly identified 

 with attack of this nature. It is a common species, and in addi- 

 tion to various garden crops seems to revel in onions. A 



