GRAPE-BERRY MOTH IN NORTHERN OHIO. 35 



closely resembled the grape-berry moth larvae. A quantity of the 

 leaves were collected on August 25, 1916, and placed in battery jars 

 containing no other food for the larvae. The larvae at the time of 

 collection varied from less than half-grown to nearly mature speci- 

 mens. The leaves dried out but the larvae completed their feeding 

 and cocooned in the leaves, a total of 79 cocoons being secured. 

 Pupae from this material were identified by August Busek of the 

 U. S. Bureau of Entomology as Polyclirosis viteana Clem. The pupae 

 were kept over winter under outdoor conditions and 12 moths emerged 

 the following spring. In a single instance an empty eggshell was 

 found on the under surface of the leaves close to a phylloxera gall. 

 In the observation made on October 2, 1917, about 1 leaf in 5 had the 

 web formed by the larvae which were feeding on the galls. In no 

 case could it be definitely determined whether the phylloxera in the 

 galls were consumed with the gall tissue. No leaf feeding other than 

 on the galls occurred with the larvae under observation. 



CANNIBALISM AMONG GRAPE-BERRY MOTH LARV^l. 



To determine if the larvae would be cannibalistic with a restricted 

 food supply the following experiment was conducted: From field- 

 collected second-brood larvae, 40 between 4 and 7 mm. in length 

 were taken and divided into two lots of 20 each on September 14, 1917. 

 One lot was placed in a jar with 20 grapes and the other lot was 

 similarly placed with but 5 grapes. Grape leaves were provided in 

 both jars for pupation of the larvae. On November 22 the following 

 results were recorded: In the lot where 20 grapes were provided, 15 

 cocoons had been formed and 2 full-grown live larvae were present. 

 Considerable substance remained in the grapes. Careful search for 

 the other 3 individuals failed to locate them. In the lot where but 

 5 grapes were supplied, 5 cocoons had been formed, 2 dead and 2 live 

 larvae were present, or a total of 9 accounted for." A careful search 

 was made for the head shields of the other 11 larvae but they were 

 not to be found. All the pulp from all the grapes had been consumed. 

 From this single experiment it appears that cannibalism exists 

 among the larvae when the food supply is restricted and may occur 

 even with sufficient food present for all. 



LARV^ NOT KILLED BY LOW TEMPERATURES. 



The resistance of grape-berry moth pupae to severe winter condi- 

 tions has been noted. On October 30, 1917, a severe freeze occurred 

 in northern Ohio, sufficient to freeze Concord and Catawba grapes. 

 The lowest temperature recorded at the Sandusky station of the 

 United States Weather Bureau on October 30 was 25° F., 26° on 

 October 31 and November 1, and 28° on November 2. When 

 recording the results of spraying experiments at Put-in-Bay, Ohio, 



