460 U. S. NATIONAL MUSEUM BULLETIN 211 



but apparently was not impressed by this gallant show, for she rudely 

 flew away and left him to deflate himself all alone. Then he flew off 

 in pursuit of her." 



Friedmann (1925) gives a slightly different account of the courtship: 



On May 6, a pair of Red-eyes was found in a field and the male watched dis- 

 playing to the female. He ruffled up the feathers of his cape or mantle first and 

 then all the feathers both on the upperparts and the underparts, brought his tail 

 stiffly forward and under, arched his wings slightly, (not more than half as far as 

 it was possible to arch them), and instead of bowing over forwards as does the 

 male of the ordinary Cowbird, merely bent his head so that his bill was touching 

 the feathers of his breast for its full extent. Then he suddenly bounced up and 

 down four times, each bounce taking him about an inch from the ground. While 

 bouncing up and down he gave a series of three very deep, guttural, yet bubbling 

 sounds, and then a set of two short and one long squeaky, thin, high notes quite 

 similar to the song of the ordinary Cowbird but wheezier, more throaty and 

 shorter. Occasionally he did bow forward a little, but nothing like the extent 

 to which M. ater does. 



The sexual and territorial relations of the red-eyed cowbird are not 

 well known. J. C. Merrill (1877), near Brownsville, Tex., found them 

 scattered over the "surrounding country in little companies of one or 

 two females and half a dozen males." Friedmann (1929) states: "In 

 this species the males outnumber the females to a somewhat greater 

 degree than in any other Cowbird as far as I know. During my field 

 work in southern Texas I saw remarkably few females compared to 

 the number of males noticed. * * * 



"That the males establish singing trees and territories is certain as 

 I have noted in several instances that certain males were to be found 

 every day in the same tree." 



Nesting. — Merrill (1877) gives us our first information on the 

 nesting of this cowbird, of which he says: 



My first egg of M. seneus was taken on May 14, 1876, in a Cardinal's nest. 

 A few days before this a soldier brought me a similar egg, saying he found it in 

 a Scissor-tail's (Milvulus) nest; not recognizing it at the time, I paid little atten- 

 tion to him, and did not keep the egg. I soon found several others, and have 

 taken in all twenty-two specimens the past season. All but two of these were 

 found in nests of the Bullock's, Hooded, and small Orchard Orioles (Icterus spurius 

 var. affinis) . It is a curious fact that although Yellow-breasted Chats and Red- 

 winged Blackbirds breed abundantly in places most frequented by these Cow- 

 birds, I have but once found the latter's egg in a Chat's nest, and never in a 

 Red-wing's, though I have looked in very many of them. * * * On six occasions 

 I have found an egg of both Cowbirds in the same nest; in four of these there were 

 eggs of the rightful owner, who was sitting; in the other two the Cowbird's eggs 

 were alone in the nests, which were deserted. * * * But the most remarkable 

 instance was a nest of the small Orchard Oriole, found June 20, containing three 

 eggs of aeneus, while just beneath it was a whole egg of this parasite, also a broken 

 one of this and of the Dwarf Cowbird. 



Friedmann (1929) writes: "The Red-eyed Cowbird victimizes rela- 

 tively few species of birds. The various species of Orioles seem to be 



