HOST RELATIONS OF PARASITIC COWBIRDS 181 



a similar occurrence since then. Dr. T. C. Meitzen (in litt.) informed 

 me that he found a parasitized nest at Refugio, Texas. The chat in 

 the lower Rio Grande Valley is of the race I.v. auricollis; the parasite, 

 T.a. aeneus. 



Rufous-capped Warbler 



Basileuterus rufifrons (Swainson) 



This warbler has recently been added to the list of hosts by J. 

 Stuart Rowley (mss.), who found a parasitized nest at Canon de 

 Lobos, Morelos, July 15, 1960. The local race of the warbler is B.r. 

 dugesi; the cowbird is of the nominate race T.a. aeneus. 



Mexican Cacique 



Cassiculus melanicterus (Bonaparte) 



At Tehuantepec, Oaxaca, Mexico, on June 11, 1955, Dr. Travis C. 

 Meitzen (in litt.) collected a nest of this cacique containing 4 eggs 

 of the owner and 1 of a bronzed cowbird. R. W. Dickerman (1960, 

 p. 473) found a parasitized nest five miles southwest of Naudreete, 

 Nayarit, on July 13, 1956. Two races of the bronzed cowbird are 

 involved in these records, T.a. assimilis in Oaxaca, and T.a. milleri 

 in Nayarit. 



Redwinged Blackbird 



Agelaius phoeniceus (Linnaeus) 



I have learned of only four instances of parasitism by the bronzed 

 cowbird on the redwinged blackbird. Two records are based on sets 

 of eggs in the J. P. Norris collection. One was taken at Camargo, 

 Tamaulipas, June 29, 1890, by T. H. Jackson; the other, in Hidalgo 

 County, Texas, May 18, 1889, by J. A. Single. Dr. T. C. Meitzen has 

 two parasitized sets of eggs from Refugio, Texas, in his collection. All 

 four of these records refer to the race A.p. megapotamus of the host and 

 to the nominate race of the parasite. There is some evidence that the 

 redwinged blackbird is usually unmolested; at least, considerable 

 numbers of its nests, examined around Brow^nsville, Texas, failed to 

 reveal any eggs of the bronzed cowbird although that bird was locally 

 fairly numerous. 



Orchard Oriole 



Icterus spurius (Linnaeus) 



The orchard oriole was designated by Merrill (1877) to be a frequent 

 host of the bronzed cowbird in the lower Rio Grande Valley, Texas. 

 R. W. Quillen found it to be parasitized at San Antonio and in Kleberg 

 County, Texas; Meitzen (in litt.) had the same experience at Refugio, 

 Texas. In the J. P. Norris collection there was a parasitized set of 

 eggs collected at Camargo, Tamauhpas. The records involve the 

 nominate race of the parasite. 



