26o MAINE AGRICULTURAL EXPERIMENT STATION. I915. 



Ictis in connection with the blueberry, nor does the writer know 

 whether as a general rule adults emerge earlier from the pu- 

 paria that are formed first. Further collections were made dur- 

 ing the past summer (1915) and it is hoped that these points 

 may be ascertained later. 



In the laboratory the adult flies were treated in accordance 

 with the suggestions given the writer by Dr. H. H. P. Severin 

 engaged in special work for this Experiment Station. They 

 were kept in glass jars about five inches high and five inches m 

 diameter in which a layer of moist sand was placed on the 

 bottom. Absorbent cheesecloth was fastened over the top, and 

 moistened with water every few hours. The adults were fed 

 with banana once a day, inserted through a hole in the cheese- 

 cloth which at other times was filled with a cotton plug. Through 

 this same hole flies could be removed or introduced at will. 

 They were supplied with a fresh blueberry twig daily. 



HOST-PLANTS. 



The writer has bred Rhagoletis pomonella Walsh from the 

 three species of low blueberries, Vaccinium pennsylvanicum, V. 

 canadense and V. vacillans. Professor OTCane has recorded it 

 from V. coryrnbosum (N. H. Exp. Sta. Bui. 171, p. 18). This 

 species has not been found at work in the mountain cranberry, 

 V. Vitis-Idaea var. minus, locally common on the plains. The 

 huckleberry, Gaylussacia baccata is also common on the barrens 

 and is subject to attack later in the season. The writer has 

 never found maggots in huckleberries in August but when the 

 blueberries are becoming scarce in early September, then the 

 huckleberries are quite generally infested. Twice before the 

 apple maggot has been reared from huckleberries {Gaylussacia 

 sp.) : once in Connecticut by Doctor Britton (Rpt. Conn. Sl3. 

 1905, p. 200) ; and once in New Jersey by Doctor Smith (In- 

 sects of N. J., 1909, p. 802). Chokeberry, Pyrus mclanocarpa, 

 is locally abundant on the plains but a careful search has failed 

 10 reveal any larvae in them. The writer did succeed in making 

 successful transfers and very small larvae removed from huckle- 

 berries and blueberries attained their growth and formed pu- 

 paria when placed in chokeberries. Puparia were also obtained 



