188 THE CANADIAN ENTOMOLOGIST 



were used in each case, viz., 1 pound to 25 of filler and 1 pound to 

 50 of filler, the bait being scattered broadcast at the rate of 10 lbs. 

 per acre. The applications were made late one evening, and counts 

 made the following morning with the following results: 



Paris green and bran, 1-25 76.3% worms dead. 



Paris green and bran, 1-50 ;... .65.7% worms dead. 



Paris green and sawdust, 1-25 55.5% worms dead. 



Paris green and sawdust, 1-50 57.1% worms dead. 



Examinations made two days after the application showed 

 approximately 75% value in the sawdust bait area and practically 

 all were dead in the bran bait area, and approximately the same 

 results were obtained by using these baits in the furrow plowed 

 around the field. 



The continuation of these experiments has been possible 

 through the courtesy of Prof. C. G. Woodbury, Director of Purdue 

 Agricultural Experiment Station, who placed at our disposal space 

 in the station greenhouse and during the months of January and 

 February, 1918, 95 individual experiments were conducted with a 

 view to determining the relative value of sawdust in comparison 

 with bran, different kinds of arsenicals, and varying formulae. 

 The insect used in these tests was the common army worm (Cirphis 

 Mnipiincta) and the method adopted was somewhat as follows: 

 enamel trays 4x8 and 3" deep were used, these being banded 

 on the inside with tree tanglefoot to prevent escape of worms. 

 Twelve army worms were used in each cage, and a small amount 

 of poison material together with a similar amount of a comparable 

 bait unpoisoned and wheat foliage was placed in the cage, giving 

 the worms every possible opportunity to utilize the unpoisoned 

 bait or foliage if they so desired. The results may be summarized 

 as follows: Of the 18 individual experiments representing 216 

 larvae, where the comparative value of bran and sawdust was 

 tested, we found 52.5% of the worms killed where sawdust was 

 used as a filler and 86.1% where bran was used. In the same num- 

 ber of experiments testing a half and half bran and sawdust mixture 

 in comparison with bran alone we found 72.5% killed where the 

 combination was used, and 90.7% where bran alone Was the filler. 



