120 U.S. NATIONAL MUSEUM BULLETIN 23 3 



a three-storied nest; each of the lower two stories contained a cowbird 



egg- 

 Since some of the western races of the yellowthroat are recorded 



only sparsely, it may be worthwhile to mention two instances that 

 have not been referred to in my earlier lists. The race campicola 

 has been recorded as a host of the western form of the brown-headed 

 cowbird, artemisiae, in eastern Washington (Jewett, Taylor, Shaw, 

 and Aldrich, 1953, p. 594). An additional record for the subspecies 

 occidentalis comes to me from Mr. K. Kreuger, who has in his collec- 

 tion a set of 2 eggs of this race of the yeUowthroat with 1 of the 

 cowbu-d, collected at Canston, British Columbia, on June 6, 1948, 

 by W. L. Maguu-e. 



The northeastern subspecies, G.t. hrachydactylus , is known to 

 be a fairly frequent victim of the eastern race of the brown-headed 

 cowbird. Aside from earher records (when the host was listed as 

 G.t. trichas), it should be noted that, in southern Quebec, 8 out of 

 113 nests, or 7 percent, which were found by L. M. Terrill (1961, 

 p. 8) between 1897 and 1956, were parasitized. 



Rio Grande Ground Chat 



Chamaethlypis poliocephala (Baird) 



There is a single record for this species (nominate race) as a host 

 of the small race of the brown -headed cowbird. F. F. Nye, Jr., 

 collected a nest containing 2 eggs of the host and 2 of the parasite 

 7 miles southeast of Brownsville, Texas, on June 19, 1944. This 

 set later was sent to A. J. B. Ku-n for the collection of birds' eggs at 

 St. Mary's University in San Antonio, Texas. 



Yellow-breasted Chat 



Icteria virens (Linnaeus) 



The yellow-breasted chat is imposed upon frequently by the brown- 

 headed cowbu-d, but the degree to which it is affected appears to vary 

 very much locally. In some areas it is said to be one of the chief 

 victims; in others it is molested only occasionally. About 180 records 

 have been noted, ranging from Canada — Ontario, Saskatchewan 

 (Potter, 1935), British Columbia— and the United States — Arkansas, 

 Arizona, Cahfornia, Connecticut, Delaware, Illinois, Indiana, Iowa, 

 Kansas, Kentucky, Maryland, Massachusetts, Michigan, Minnesota, 

 Missouri, Montana, Nebraska, Nevada, New Jersey, New York, 

 North Carolina, Ohio, Oklahoma, Pennsylvania, South Dakota, Texas, 

 Virginia, Washington, and Wisconsin — to northwestern Mexico in the 

 state of Sonora, near Granados (A. PhiJlips, in htt.). There are 

 numerous records for both races of the chat, virens and auricoUis, and 



