428 Phylum Arthropoda 



are more favorable for the earthworms and probably for the dipterous 

 larvae. Both must be kept moist. 



Pupation occurs in the soil. The pupa should be removed to drier 

 soil. The life cycle is about 30 days. 



The best and most abundant generation with which to work is the 

 hibernating generation, but there is a summer generation appearing the 

 latter part of May at Urbana, after which the flies gradually become more 

 common until the large hibernating generation appears toward the 

 latter part of September. 



Bibliography 



DeCoursey, R. M. 1927. A bionomical study of the cluster fly, Pollenia rudis Fab. 



Ann. Ent. Soc. Amer. 20:368. 

 1932. The feeding habits of the first instar larvae of the cluster fly. 



Science 75:287. 

 Garrison, G. L. 1924. Rearing records of Pollenia rudis Fab. Ent. News. 35:135. 

 Keilin, D. 191 1. On the parasitism of the larvae of Pollenia rudis Fab. in 



Allolobophora chlorotica Savigny. Proc. Ent. Soc. Wash. 13:182. 

 1915. Recherches sur les larves de Dipteres Cyclorhaphes. Bidl. Sci. France 



Belgique 49:15. 

 Webb, J. L., and Hutchinson, H. H. 1916. A preliminary note on the bionomics 



of Pollenia rudis Fab. in America. Proc. Ent. Soc. Wash. 18:197. 



Family muscidae 



j 



stomoxys calcitrans 



Roy Melvin, U. S. Bureau of Entomology and Plant Quarantine 



THE stable fly, Stomoxys calcitrans, has been reared in captivity 

 through many successive generations by the following method. 



Feeding and care of adidts. The cage is 2 x 3 feet and 2 feet high. 

 Both sides, the top, and one end are made of 16-mesh galvanized screen- 

 ing. The bottom and one end are made of i-inch pine. A hole 10 inches 

 in diameter is cut in the solid end of the cage, in which a cloth sleeve 

 is attached. 



The adults are fed water by means of a fountain [see p. 432], honey 

 every other day, [see p. 409], and guinea pig blood once a day. The 

 guinea pig is fastened to a board 6 inches wide and 12 inches long by 

 means of four soft strings, one around each foot, which pass through 

 %-inch holes in the board and fasten to a binding post at the end of the 

 board. By this method the guinea pig can stand or recline but cannot 

 kill or dislodge the engorging flies. It has been found that if a guinea 

 pig is allowed to remain in the cage for 2 hours each day the flies will 

 obtain enough blood to carry on normal life processes; that is, to mate 

 and lay fertile eggs. 



