July, 1914.] THE APPLE MAGGOT. 59 



Cage 4, 7 flies. Apple leaves offered dipped in solution of 

 glucose 2 parts, water 8 parts, arsenate of lead as in cages 1 and 

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



Cage 5, check, 6 flies. No apple leaves dipped in solution were 

 offered. Eecord: 5 flies dead at the end of four days; remaining 

 fly sluggish and removed. 



To see if further information might be secured, use was made 

 of the flies emerging in three of the concrete bins, by offering in 

 each case a branch of apple leaves dipped in a solution of glucose, 

 water, and arsenate of lead. The presence of the sweet appar- 

 ently had no appreciable effect on the behavior or welfare of 

 the flies. On occasion, flies would be observed on the leaves, but 

 they seemed not to be attracted to them in any noteworthy 

 fashion, and no special results were discernible from such atten- 

 tion as they paid them. 



Other Corroborative Experiments, The long-continued ex- 

 periments with poison bait sprays described later in this bulle- 

 tin are essentially field tests on an extended scale of the response 

 of the flies to the ordinary sweetened baits. The results of these 

 tests are believed by the writer to offer conclusive data on the 

 subject. 



Harvey (25 p. 223) described tests of baits tried by him. A 

 bait was prepared of sweets poisoned with arsenious acid and 

 corrosive subhmate. This was placed on paper in shallow pans 

 in the trees. It failed to attract the flies. Sticky fly paper was 

 tested, several sheets being hung in the branches of a tree where 

 flies were numerous. Only one apple maggot fly was caught. 



Ross (55 p. 68) tried poisoned molasses spread on the branches; 

 also tanglefoot traps sprayed with the essence of pear, peach 

 and banana, and with citronella oil; and tin pans containing 

 poisoned cider, essence of pear, citronella oil, and kerosene. No 

 results were obtained, except with kerosene, when 7 pans caught 

 a total of 28 flies. 



GENERAL BEHAVIOR OF ADULTS. 



Perhaps the most notable characteristic of the adult flies is 

 their sluggish behavior. They are not normally active or 

 nervous. It is seldom difficult to capture a specimen by quietl}' 

 placing the open mouth of a small vial over it as it rests on a leaf 



