HOST RELATIONS OF PARASITIC COWBIRDS 159 



Reservation, ten miles south of Tucson, Ai'izona, he found two para- 

 sitized nests, and that, in the University of Arizona collection, there is 

 still a third such case, collected in the same area by P. J. Gould. 



Bachman's Sparrow 



Aimo-phila aestivalis (Lichtenstein) 



This is an uncommonly victimized sparrow; only the following 

 few records have been noted. 



E. S. Woodruff (1907, p. 349) found a nest in southern Missouri on 

 May 27, 1907, containing 2 sparrow and 3 cowbird eggs. This record 

 relates to the race A.a. illinoensis of the sparrow. 



Near Bardstown, Kentucky, Blincoe (1921, p. 100) on May 2 found 

 a nest which at the time contained 1 sparrow egg. The next day the 

 nest held 1 cowbird and 2 sparrow eggs ; two days later all the eggs had 

 disappeared, apparently having been removed by some predator. In 

 a later paper the same author (1925, p. 412), discussing the cowbird at 

 Bardstown, states that its eggs were found in nests of Bachman's 

 sparrow and the indigo bunting. It is not clear whether or not 

 Blincoe had seen additional instances of cowbird parasitism on Bach- 

 man's sparrow in the four years between the two reports. 



Brooks (1938a, p. 100) reported a nest with 3 eggs of the sparrow and 

 1 of the cowbird at French Creek, West Virginia. 



The Kentucky and West Virginia records refer to the race A.a. 

 baclimani of the host. In all the above cases the nominate race of 

 the parasite is involved. 



Cassin's Sparrow 



Aimophila cassinii (Woodhouse) 



Cassin's sparrow appeal's to be an infrequent victim of the brown- 

 headed cowbird. The known records are few enough to be listed here. 



R. W. Quillen wrote me that at San Antonio, Texas, Cassin's spar- 

 row rarely was bothered by the parasite, probably because the former 

 concealed its nests so well. This, however, might explain why the 

 nests were not found more often by human eyes than by the cowbird. 

 Quillen found only three parasitized nests. The late J. H. Bowles 

 wrote me that he had in his collection a similar set from San Antonio; 

 the U.S. National Museum has two more sets from the same place, 

 collected by H. P. Attwater. Finally, E. J. Court informed me that 

 he also found this sparrow to be victimized near San Antonio. Nye 

 (in litt.) informed me that he collected a parasitized set of eggs near 

 Loma Alta Lake, nine miles north of Brownsville, Texas, on June 21, 

 1943. In the files of the U.S. Fish and Wildlife Service there is the 

 record of a parasitized nest found 30 miles south of Vernon, Texas, 

 on May 2, 1930, by R. L. More. All of these records refer to the small 



