696 AN INTRODUCTION TO ENTOMOLOGY 



the flowers of the evening primrose. The hind wings are white. 

 The fading petals of the primrose turn pinkish, and the pink color of 

 the closed fore wings renders the moth invisible when in old flowers, 

 while the yellow tips of the fore wings protruding from a flower still 

 fresh and yellow, forms an equally perfect protection from observa- 

 tion. This moth in its passage from flower to flower transports pollen 

 and is the special means of insuring the cross-fertilization of the even- 

 ing primrose. It attaches its eggs to the stalks of the flower buds or 

 near them. The larvag feed on the petals of the flowers and bore 

 into the buds and seed-vessels. They are bright green, covered with 

 numerous, elevated, white granules; when full-grown they measure 

 30 mm. in length. Their color is protective. There is a single genera- 

 tion each year. 



Cttt worms.- — ^Few pests are more annoying than the rascally little 

 harvesters that nightly, in the spring, cut off our com and other 

 plants before they are fairly started. There are many species of these 

 cut-worms, but they are all the larvae of owlet-moths. In general 

 their habits are as follows: The moths lay their eggs during mid- 

 summer. The larvae soon hatch, and feed upon the roots and tender 

 shoots of herbaceous plants. At this time, as the larvae are small and 

 their food is abundant, they are rarely observed. On the approach 

 of cold weather they bury themselves in the ground and here pass 

 the winter. In the spring they renew their attacks on vegetation; 

 but now, as they are larger and in cultivated fields the plants are 

 smaller, their ravages quickly attract attention. It would not be so 

 bad if they merely destroyed what they eat; but they have the un- 

 fortunate habit of cutting off the young plants at the surface of the 

 ground, and thus destroy much more than they consume. They do 

 their work at night, remaining concealed in the ground during the 

 daytime. When full-grown they form oval chambers in the ground 

 in which they pass the pupa state. The moths appear during the 

 months of June, July, and August. 



There are some exceptions to these generalizations : some species 

 of cut -worms ascend trees during the night and destroy the young 

 buds ; many pass through two generations in the course of a year ; 

 and a few pass the winter in the pupa state. 



Cut -worms can be destroyed by poisoned baits of fresh clover or 



other green vegetation, or with poisoned dough made of bran. 



Much can be done by making holes in 



the ground with a sharpened stick, as 



a broom-handle. The holes should be 



vertical, a foot deep, and wnth smooth 



sides. On the approach of day the cut- 



woims will crawd into such holes to hide 



and will be unable to crawl out again. 



Fig. 87g.-~Agrotis c-nigrinn. One of our cut-worms, which is 



known as the spotted cut-worm, is the 



larva of the black-c owlet, A gratis c-nigrum. This moth (Fig. 879) 



is one of the most common species attracted to lights. It occurs 



throughout our country and in Europe. 



