16 BULLETIN 432, U. S. DEPARTMENT OF AGRICULTURE. 



Lakeland, Fla., in May, 1913, and by H. E. Smith at Greenwood, 

 Miss., in May, 1914. The species was described by Crawford 1 

 (p. 183) from specimens under Webster No. 7286, Tempe, Ariz. 



Polycystus foersteri Cwfd. (PL I, fig. 6). — This species was reared 

 from C. dorsalis in corn by G. G. Ainslie, May, 1913, at Orlando, 

 Fla., and was reared from C. dorsalis in barley by E. L. Barrett at 

 Pasadena, Cal., on June 6, 1915. This parasite was described as 

 a new species by Crawford (Proc. U. S. Nat. Mus., v. 45, p. 313) in 

 1912, from specimens reared by the senior author from Agromyza 

 angulata at La Fayette, Ind. 



Dacnusa n. sp. — This species was reared April 25, 1914, from a 

 puparium of C. dorsalis removed from Hordeum murinum taken at 

 Glendale, Cal., and on May 1 and 2, 1914, it emerged from puparia 

 of Cerodonta dorsalis removed from barley at the same localit} T . It 

 was reared on January 3, 1915, by E. L. Barrett from a puparium of 

 C. dorsalis removed from a barley leaf at Pasadena, Cal. 



Chrysocharus parksi Cwfd. — This species was reared by T. D. 

 Urbahns, the junior author, June 16, 1914, from a puparium of C. 

 dorsalis removed from a leaf of wheat taken at Yisalia, Cal. The 

 species was described by Crawford 1 (p. 173). 



Opius dimidiatus Ashm. — The senior author reared one adult 

 of this species from C. dorsalis mines in millet at La Fayette. Ind.. 

 in 1912. This species is also recorded as a parasite of A. pusUlar 



Opius aridus Gahan. — Mr. G. G. Ainslie reared this species from 

 mines of C. dorsalis in corn at Lakeland, Fla. This species is also 

 an enemy of Agromyza pusilla. 3 



PREVENTIVE MEASURES. 



Owing to the concealed character of damage and method of work- 

 ing, this insect has not attracted widespread attention, and no de- 

 mands have been made concerning control methods. It would 

 appear, however, that the practice of summer fallowing in the West 

 would do much to destroj 7 puparia remaining in the dry leaves. 



Fall plowing and, in fact, any thorough cultivation of grain fields 

 to destroy the remaining stems and leaves as well as volunteer grain 

 should destroy such of this species as remain in the larval and pupal 

 stages. 



Burning of dry grasses along fence lines, roadsides, and terraces 

 in late fall and early spring should likewise destroy some of the 

 puparia. 



1 Crawford, J. C. Descriptions of new Hymenoptera. In Proc. U. S. Nat. Mus., v. 43, 

 p. 163-188. 1912. 



2 Crawford, J. C. Descriptions of new Hymenoptera. In Proc. U. S. Nat. Mus., v. 45, 

 p. 309-317. 1913. 



3 Webster, F. M., and Parks, T. H. The serpentine leaf-miner In Jour. Agr. Res., v. 1, 

 no. 1, p. 59-88, pi. 5, fig. 1-17. 1913. 



