272 U. S. NATIONAL MUSEUM BULLETIN 211 



tions and two or three long horse hairs it was composed wholly of wild oats and 

 rather loosely woven. A few of the oat heads show on the inside where they 

 were worked into the nest itself, but almost all are on the outside, the long stems 

 being worked in to their heads which stood out in a beautiful and graceful fringe 

 all around and below for from one to three inches or more. The effect was 

 striking and unusual. * * * The dimensions in inches are as follows: Depth 

 outside (extreme) 14; depth outside (front) to opening, 8; depth inside to opening 

 5^; diameter outside, 7; diameter inside, 4; circumference 21. 



J. F. Illingworth (1901) writes: 



Until the season of '97 I have never known the Bullock's Oriole to use palm- 

 fiber in the construction of its home, but I found a nest May 11, 1897, in a peach 

 tree, composed entirely of this fiber. It was well lined with chicken feathers and 

 placed between several small branches. A pair of Bullock's Orioles built a nest 

 this year in an almond tree near the porch, and I had an excellent opportunity to 

 watch them while they were at work. The place chosen was in a wide fork be- 

 tween four small branches. Both birds worked on the nest and as soon as they 

 had loosely formed the walls or framework, one of them worked inside and the 

 other outside. The latter would bring a horse-hair or a piece of twine in its 

 beak and pass the end through the wall of the nest to his mate inside who took the 

 end and passed it out again through another place. In this way the nest was 

 soon woven quite smooth and looked as if it had been made with a darning needle 

 by hand. 



Eggs. — Bullock's oriole lays from three to six eggs to a set; four 

 and five are the commonest numbers, but sets of six are not rare. 

 Bendire (1895) describes them as follows: 



The eggs are mostly elongate ovate in shape, a few are ovate, and an occasional 

 set is almost wedge-shaped or cuneiform. The shell is close grained and only 

 slightly glossy. The ground color is generally of the same subtle grayish-white 

 tint as that seen in the eggs of the Baltimore Oriole, but the proportion of the 

 pale bluish white eggs is greater than with the latter. Occasionally the ground 

 color is pale vinaceous buff. The markings are similar in color to those found on 

 the eggs of the preceding species [Baltimore oriole], but as a rule they are not so 

 coarse, and the fine hair lines running in irregular tracings around the larger axis 

 of the egg are more prevalent; they are also a trifle larger. 



The average measurement of 144 specimens in the United States National 

 Museum collection is 23.80 by 15.93 millimetres, or about 0.94 by 0.63 inch. 

 The largest egg in the series measures 25.40 by 16.76 millimetres, or 1 by 0.66 

 inch; the smallest, 21.34 by 15.24 millimetres, or 0.84 by 0.60 inch. 



Young. — Bendire (1895) states: "Only one brood is raised in a 

 season, and the duties of incubation, which are performed almost 

 exclusively by the female, last about 14 days. I have often watched 

 the sitting bird, and have never seen the male on the nest." 



Mrs. Wheelock's (1904) observations confirm this statement; and 

 she adds: 



Her mate is always within calling distance, keeping a vigilant watch for squir- 

 rels, crows, and jays; and should any of these enemies appear, not only he but the 

 mother bird, joined by all the orioles and blackbirds within hearing, will fly at 

 the intruder and effectually banish him from the vicinity. When newly hatched, 

 the young orioles are naked, pink babies with little tufts of thin white down on 



