58 N. H. AGR. EXPERIMENT STATION. [Bulletin 171 



Five c.c. water containing 10 drops of 95 per cent alcohol. 

 One fly in cylinder at the end of twenty hours. 



Ten drops 95 per cent alcohol, 10 drops acetic acid and 2 drops 

 amyl valerianate. No flies in cylinder at the end of two hours. 



Twenty-three flies were used in the tests with the modified 

 apparatus. The substances tried, with the results recorded, 

 were as follows: 



Five c.c. distilled water containing 10 drops 95 per cent alcohol. 

 Xo result at end of two and a quarter hours. 



Five c.c. distilled water containing 10 drops acetic acid. No 

 results. 



Five c.c. water containing 3 drops amyl valerianate. ' No 

 results at end of two and one half hours. 



Pure coal oil. One fly in cylinder at end of three hours. 



Five c.c. water containing 1 drop acetic acid and trace of amyl 

 valerianate. Two flies in cylinder at end of one half hour. 



Experiments in 1911. In 1911 arrangements were made 



for confining flies in observation cages, and offering them leaves 

 dipped in sweet solutions that might prove attractive. With 

 these solutions was mixed arsenate of lead in the same proportion 

 used in some of the field tests of poison bait sprays. 



The flies were secured from large numbers of adults emerging 

 in the concrete bins in the open-air insectary. Infested apples 

 had been placed on earth in these bins the previous season. 

 Emergence of the flies began a few days early, apparently being 

 somewhat accelerated by the warmth absorbed by the concrete 

 l)ins, which, earlier in the season, had been exposed to sunHght. 



The cages were 12 by 12 by 24 inches, with glass fronts and 

 cheese-cloth sides. The flies were provided with water. 



June 19 and 20, 1911, the following cages were started, with 

 the results indicated: 



Cage 1, 10 flies. Leaves offered were dipped in a solution of 

 molasses 1 part, water 4 parts, arsenate of lead at the rate of 1 

 ounce to 1 gallon. Record: alb flies dead at the end of five days. 



Cage ,2, 8 flies. Leaves offered were dipped in a solution of 

 molasses 2 parts, water 4 parts, and arsenate of lead as before. 

 Record: all flies dead at the end of five days. 



Cage 3, check, 10 flies. Apple leaves offered, but not dipped 

 in any solution. Record: all flies dead at the end of five days. 



