Alfalfa Looper 



The eggs are deposited on the food plants. Moths have been ob- 

 served in the act of laying at three o'clock in the afternoon.* 



The Caterpillar 



These caterpillars differ from all others discussed in this Bulletin 

 in having but three prolegs on each side of the posterior half of the body. 

 By comparing Figure 1 and Figure 5, Plate VI, Page 21, this difference is 

 made more apparent. It will be noticed that Figure 1 has four legs just 

 back of the center, and one at the tip of the body, and that Figure 5, which 

 represents a full grown alfalfa looper, has but three including the one at 

 the tip. 



The alfalfa loopers vary greatly in color. 



The darker parts of different individuals range from a dark olive 

 brown to pale greenish brown. The figure represents one of the lighter 

 type. 



The Cocoon 



The cocoon (Fig. 6, Plate VI, Page 21) is made of several leaves of 

 the host plant held together by loosely woven silk threads. Sometimes 

 the cocoons are constructed among dead leaves and trash on the ground. 



The Pupa 



After the worm has completed its cocoon it changes to the pupa 

 within it. The pupa (Fig. 7, Plate VI, Page 21) is very similar to those 

 of the cutworms and army worms. 



The Moth 



The adult (Fig. 8, Plate VI, Page 21) is one of our most beautiful 

 moths. The figure is so true to life that no description is necessary. 

 The silvery spot near the center of the fore wing is characteristic of this 

 and related moths. 



LIFE HISTORY 



This insect probably passes the winter in hibernation in the pupal 

 stage. During the latter part of May and early June the eggs for the first 

 brood of worms of the season are laid. 



The length of the egg stage is not definitely known. The worms 

 feed for about two weeks, at the end of which time the cocoon is made 

 and the change to the pupal stage takes place. This lasts about ten to 

 twenty days during ordinary summer weather. 



The first adults of the second brood appear during late June and early 

 July. There are two and possibly three generations each season. 



NATURAL ENEMIES 



The alfalfa looper appears to be a favorite host of many parasites. 

 The Ichneumon-fly 8 , shown in Figures 9 and 10, Plate VI, Page 21, was 

 reared from alfalfa loopers taken at Edgar, Montana, and several other 

 species have been reared from alfalfa loopers by Mr. Hyslop. 



Many of the caterpillars succumb to a bacterial disease. The in- 

 fected worms become dark in color soon after dying. The dead worms 



*Mr. Koebels. Bureau of Entomology Notes. No. 95-K. 

 (") See explanation of "Reference Figures." page 2. 



83 ! 



