THE CANADIAN ENTOMOLOGIST. 313 



arsenite was used instead of arsenate of lead. Different quantities 

 of a number of brands of arsenate of lead were used, but many 

 onion flies were still alive at the end of a week, even though the 

 bait was renewed daily. The following formula was used: 



Molasses % pt. 



Sodium arsenite J4 oz. (dissolved in boiling water). 



Water 1 gall. 



The results obtained against the second brood of the pest 

 were most encouraging in a somewhat isolated onion field. As the 

 season's work was started too late to test the effectiveness of the 

 poisoned bait against the first brood of the pest, which is probably 

 more difficult to combat on account of the frequent spring rains 

 which wash off the spray, no definite conclusions can be drawn 

 from the good showing that the spray has made against the second 

 brood. 



References. 



1. Betanzos, D. J., 1905. — Report of the Commissioner Ap- 

 pointed to Investigate the Prevalence of Trypeta ludens in Mexico. 

 Cal. State Hort. Comra., pp. 31-33. 



2. Chapelle, J., and Ruby, J., 1907-11. — La Lutte contre la 

 Mouche de l'Olive. Resultats des Experiences Organisees en 

 France en 1907, 1908, 1909, 1910 et en 1911 par le Service de 

 l'Oleiculture. Extrait du Bulletin mensuel de l'Office de renseine- 

 ments agricoles, decembre 1907 et aout 1908, pp. 1-19, Janvier et 

 decembre 1910, pp. 1-8 et 1-5, Janvier 1912, pp. 1-5. 



3. Chapelle, J., and Ruby, J., 1913. — La Lutte contre la 

 Mouche de l'Olive. Annee 1912. La Petite Revue Agricole et 

 Horticole, Janvier pp. 2-3. 



4. Dreyer, T. F., 1907. Poisoned Bait for the Fruit Fly. 

 Repr. Agric. Jour., Feb., No. 5, Cape of Good Hope, pp. 1-4. 



5. Fuller, C, 1909-10.— 7th Rept. Gov. Ent., Dept. Agric. 

 Natal, p. 26. 



6. Illingworth, J. F., 1912.— A Study of the Biology of the 

 Apple Maggot (Rhagoletis pomonella), together with an Investiga- 

 tion of Methods of Control. Cornell Univ. Agric. Exp. Sta., Bull. 

 324, pp. 163-171. 



7. Illingworth, J. F., 1912. — Cherry Fruit Flies and How to 

 Control Them. Ibid., Bull. 325, pp. 199-202. 



8. Johannsen, O. A., and Patch, E. M., 1911. — Insect Notes 

 for 1911. Maine Agric. Exp. Sta., Bull. 195, p. 238. 



