HOST RELATIONS OF PARASITIC COWBIRDS 143 



serted by the buntings during the egg-hiying period. He suggests 

 that nest desertion occurs if the nest is parasitized early in egg-laying 

 before the third or fourth egg of the host is laid. No nest had more 

 than 2 cowbird eggs and, in at least two nests, young of both parasite 

 and host matured to the fledgling, nest-departing stage. 



More records of cowbird parasitism on this bunting are from Texas 

 than elsewhere. Besides Quillin's statement, mention should be 

 made, among others, of Nye (1939, p. 87), Simmons (1925, p. 172), 

 and Savary (1936, p. 62). 



Dickcissel 



Spiza americana (Gmelin) 



The dickcissel is a not uncommon victim of the brown-headed cow- 

 bird. About 55 instances have been reported from Arkansas, Illinois, 

 Indiana, Iowa, Kansas, Michigan, Nebraska, Oldahoma, and Texas. 

 In southern Texas, it is parasitized by the small race of the cowbird, 

 obscurus; elsewhere, by the eastern race, ater. R. W. Quillin in- 

 formed me many years ago that around San Antonio, Texas, he 

 had examined hundreds of dickcissel nests and had found cowbird 

 eggs in only four cases. Philo Smith, Jr. (1882, p. 182), reported 

 as many as 4 cowbird eggs with 3 of the owner in one dickcissel 

 nest. This species is not bothered by the cowbirds to the same 

 degree that some other ground-nesting birds are. Judging by the 

 published records, it appears to be imposed upon more often in 

 Texas, Oklahoma, Nebraska, and Kansas than elsewhere. In addition 

 to Quillin's San Antonio records, there are others from Texas — the 

 Austin area (Simmons, 1925, p. 172) and Brenham (Nye, 1929, 

 p. 87). In 1907 at Lawrence, Kansas, Hanna collected three para- 

 sitized sets which are now in the collections of the California Academy 

 of Sciences. According to information received from R. F. Johnston 

 (in litt.), 6 out of 23 nests found in one area in Kansas were para- 

 sitized — ^an incidence of 25 percent. Overmire (1962, pp. 115-116) 

 recorded a higher frequency of parasitism in Oklahoma, where he 

 found that 19 out of 61 dickcissel nests (31 percent) contained eggs 

 of the cowbird — not one of which survived to the hatching point. 

 The highest frequency of cowbird parasitism which I have yet 

 found is 53 percent: reported in Nebraska by Hergenrader (1962, 

 pp. 85-88). 



Evening Grosbeak 

 Hesperiphona vespertina (Cooper) 



This species is included in the present list on the basis of a single 

 observation, which was made at Saranac Lake, New York, in July, 

 1949. The case already has been described in detail by Schaub 

 (1949) and by Nichols (1949). It involves a fledgling cowbird 



