552 U.S. NATIONAL MUSEUM BULLETIN 237 part i 



Mountains, mentions a nest that "was built in a slight hollow in the 

 ground at the base of a small and scraggly specimen of sage * * * in an 

 open space on the canon bottom fully twenty feet from any more 

 pretentious bush, such as we had expected to fmd this bu'd selecting as 

 a shelter for its home." Apparently the species nests in cactus at 

 times (F. M. Bailey, 1902). L. Plering (1948), among others, points 

 out that the greentail may show a preference for stream environments 

 wherever these are available. 



Although nest-building activity seems not to have been recorded, 

 there have been a number of partial descriptions of finished nests. 

 These are generally rather large, thick-walled, and fairly deeply cupped; 

 in one, as reported by J. GrinneU and T. I. Storer (1924), "the cavity 

 measured 67 millimeters across by 40 millimeters deep." The major 

 part of the structure usually includes twigs and stems, grasses, and 

 bark (including that of sagebrush); the lining comprises fine plant 

 stems, rootlets, and in most instances strands of horsehair from mane 

 or tail. Sometimes other kinds of hair, as that of the porcupine 

 (I. N. Gabrielson and S. G. Jewett, 1940), may be used. 



Sets of eggs are to be found over a period of approximately two 

 months, from Alay 20 to July 21. The median date, based on 26 

 sets, is June 17. These records pertain to findings in six states, from 

 Oregon and California to New Mexico. Some observers (R. B. 

 Rockwell and A, Wetmore, 1914; A. J. van Rossem, 1936) have sus- 

 pected that the green-tailed towhee normally has two broods, but a 

 larger compilation of nesting data or a careful study of color-banded 

 birds would seem necessary to establish this as fact. There is circum- 

 stantial evidence of a replacement nesting or second nesting attempt 

 (Allan R. PhiUips, MS.). 



One wonders what sort of role in the species' breeding program might 

 have been played by the hermaphrodite example which J. A Jeffries 

 (1883) has described in this manner: "A short time ago I received the 

 body of a Green-tailed Towhee * * *. The bird was shot by Mr. 

 Brewster, at Colorado Springs, on May 16, 1882. In plumage it 

 resembled females of the species, but on dissection to determine the 

 sex, both an ovary and a testicle were found; the one on the left the 

 other on the right side. 



"* * * the two generative mounds took on the two sexes and * * * the 

 accessory structures followed the master organs. So the Wolffian 

 duct remained on one side and the Mullerian on the other." 



Eggs. — According to notes provided by A. R. Phillips, the eggs, as 

 observed at one nest, are laid one a day in the early morning. The 

 first was known to have appeared before 10:45 on Ma}^ 27, 1936, the 

 second before 8:35 on the 28th, and the third before 8:45 on the 29th. 

 The eggs were cold throughout this period, but a bird sometimes was 



