BIRDS OF ARGENTINA, PARAGUAY, URUGUAY, AND CHILE 377 



ruary 5 to 9 (adult male, February 5) ; and Rio Negro, February 15. 

 Specimens from Uruguay appear to have slightly shorter bills* than 

 those from Buenos Aires, but the species is somewhat variable in 

 length of culmen. 



These blackbirds were found in little scattered flocks at the borders 

 of marshes or in wet localities on the open pampa, where they walked 

 about like grackles in preoccupied search for food. Thej'^ were 

 common near the beach below Cape San Antonio, Buenos Aires, and 

 many were noted about the caiiadones farther inland. During Octo- 

 ber and November the birds often scolded me as I traveled through 

 the rushes, and on November 13 I saw young recently from the nest. 

 In fall and winter it was usual for them to rest in clumps of saw 

 grass to warm themselves in the earlj^ morning sun. Their calls, 

 given usually on the wing, were musical and pleasant to the ear. 



An adult male killed October 23 had the bill and tarsus black; 

 iris sayal brown. 



AMBLYRAMPHUS HOLOSERICEUS (Scopoli) 



XantJwruiis holosericens Scopoli, Del. Flor. Faun. Ins., pt. 2, 17S6, p. 88. 

 (Islands of the Parana Delta.") 



This brilliant inhabitant of rush-grown marshes was fairly com- 

 mon in central and northern Argentina. At Las Palmas, Chaco, 

 from July 14 to 28, 1920, it was observed occasionally in flight 

 overhead, in usual blackbird fashion, and my acquaintances among 

 the people of the little village were not satisfied with my daily bag 

 of specimens until, on July 28, I had added a beautiful male to my 

 collection. An immature male with only scattered orange feathers 

 on the otherwise black head and chest was frowned upon as hardly 

 worth preservation, but to me w-as as interesting as the adult. This 

 bird is in slow molt into the adult plumage. 



These blackbirds were recorded frequently about the lagoons near 

 Kilometer 182, Formosa, August 9 to 21, and on the latter day were 

 noted in numbers in the esteros between Fontana and Formosa. A 

 few Avere found with flocks of Agelaius rwficapillus September 17, 

 near Kilometer 80, west of Puerto Pinasco, Paraguay, where a male 

 taken had nearly completed the molt into the adult stage. The spe- 

 cies was seen at Dolores, Buenos Aires, October 21, and a female 

 about to breed was shot at Lavalle, Buenos Aires, October 29. An- 

 other was noted near here November 16. One was seen at the Paso 

 Alamo on the Arroyo Sarandi north of San Vicente, Uruguay, Feb- 

 ruary 2, 1921. 



These blackbirds are found universally in marshes where often 

 the}^ rest concealed among the rushes and seem rather shy. They 



■" See Dabbene, An. Mus. Nae. Hist. Nat. Bubdos Aires, vol. 23, Dec. 26, 1912, p. 372. 

 The originaJ locality cited by Scopoli "Antigua, Panay," was in error. Brabourne and 

 Chubb (Birds South America, December, 1912, p. 436) cite Brazil. 



