82 U.S. NATIONAL MUSEUM BULLETIN 23 3 



species, out of many hundreds of nests examined by various observers, 

 have come to my notice. Mr. E. J. Court informed me that A. H. 

 Hardisty once found a cowbird's egg in a nest with eggs of the starling 

 near Beltsville, Maryland. Blocher (1933, p. 157) reported a para- 

 sitized nest at Amboy, Illinois. 



Black -capped Vireo 



Vireo atricapilla Woodhouse 



The black-capped vireo is an infrequently reported and probably 

 a fairly uncommon victim. Twelve instances of cowbird parasitism 

 on this vireo have come to my notice, involving two races of the 

 parasite, ater and obscurus. Four records from Oklahoma, three of 

 which were mentioned by Nice (1931, p. 150) and observed by G. W. 

 Morse at Tulsa, concern the nominate subspecies of the cowbird, 

 while seven from Texas (Comal and Travis Counties) involve the 

 dwarf race. One of the latter records, from Austin, includes the ob- 

 servation of a fledgling cowbird reared by a black-capped vireo; the 

 others are all egg records. 



White-eyed Vireo 



Vireo griseus (Boddaert) 



The white-eyed vireo is a fairly frequent host, first recorded in this 

 capacity by Alexander Wilson (1810, p. 166) in the early days of 

 American ornithology. The general scarcity of published data on this 

 bird is reflected in the fact that, in my first summation (1929, p. 237), 

 I was aware of about 20 records; in the 30 years or so since then, I 

 have been able to add only 37 more. The records range from Con- 

 necticut, New York, New Jersey, Pennsylvania, and Virginia to 

 Illinois, Tennessee, Georgia, Alabama, Louisiana, Texas, Oklahoma, 

 Kansas, and Tamaulipas, Mexico. Many years ago Mr. S. J. Darcus 

 informed me that he had found two parasitized nests of this vireo at 

 Fredericton, New Brunswick, in 1909 and 1910. This information I 

 published (1934, p. 34) because of its far northeastern locality, but 

 at present I prefer to consider the record somewhat doubtful for the 

 very reason of its location. Bent (1950, p. 235), nevertheless, states 

 that the breeding range of the white-eyed vireo extends to "Gasp6 

 County, Quebec (L'Anse Pleureuse); New Brunswick (Fredericton 

 and St. John, probably) . . . ." 



Although few actual cases have been put on record since Singley's 

 original instance (1888) in southern Texas, Mr. R. W. Quillin and 

 the late E. D. Camp found the local race of this vireo, V.g. micrus, 

 to be very commonly parasitized. The southernmost instance in- 

 volves a nest with 4 eggs of the vireo and 1 of the dwarf race of the 

 cowbird found at Reynosa, Tamaulipas, Mexico, May 4, 1941, and 



