386 BULLETIN 195, UNITED STATES NATIONAL MUSEUM 



the egg; in some specimens tlie spots run longitudinally. In this type about 

 three-fourths of the eggs examined can be included. They resemble, in the style 

 of marking, the eggs of Mimus polyglottos, somewhat, although the eggs them- 

 selves look quite different. In about 20 percent the ground color is somewhat 

 clouded over and partially obscured by the markings, which are finer, less pro- 

 nounced, giving the egg a uniform pearl gray and pale greenish gray appearance 

 till closely looked at. In an occasional specimen, the markings are simply fine 

 pinpoints, as in the smaller spotted eggs of Uarporhynchus rufus. 



In about 5 percent of the eggs, the ground color is grayish or pinkish white 

 with scarcely a trace of green, and the egg is heavily and uniformly spotted 

 with longitudinal markings of pale salmon color and lavender, bearing a striking 

 resemblance to some eggs of Myiadestes townsendi, excepting in size. A single 

 egg has a distinct wreath about the larger end. 



The shape of these eggs varies a great deal, the most common form being an 

 elongate ovate, varying from this to ovate, short ovate, and elliptical ovate. 



The measurements of 50 eggs in the United States National Museum 

 average 25.6 by 19.1 millimeters; the eggs showing the four extremes 

 measure 29.7 by 19.6, 28.5 by 21.8, 23.4 by 18.8, and 25.4 by 17.8 

 millimeters. 



Young. — No one seems to have determined the period of incubation 

 for this thrasher or the length of time that the young remain in the 

 nest, though Bendire's probably does not differ materially from other 

 desert thrashers in these matters. This species is so shy about its nest 

 that the care and feeding of the young are not easily observed, and 

 nothing seems to have been recorded on this subject. As mentioned 

 above, two broods in a season seems to be the rule, with sometimes a 

 third brood. Mr. Gilman (1915) noted that one pair of birds brought 

 off a brood of young about the first of May, a second brood left the nest 

 on July 6, and on July 25 the female was incubating on a third set of 

 eggs. 



Mr. Scott (1888a) says: "The young birds, as soon as they are fully 

 grown, begin to congregate in companies, often being associated with 

 one or two H. curvirostris fdlmeri and H. crissalis. I have seen forty 

 or fifty young Thrashers, mostly bendirei, together in such a flock in 

 late May and early June. At such times the birds seek a somewhat 

 higher altitude, as high as five thousand feet, and effect thickets of 

 low oaks and juniper." 



Plumages. — Young Bendire's thrashers in juvenal plumage differ 

 from the breeding adults, which are then quite worn and faded, in 

 having the upper parts, especially the rump, tinged with reddish 

 brown, the secondaries and tertials broadly edged and tipped with 

 buffy brown, the greater wing coverts broadly tipped with "cinnamon- 

 buff," and the tail feathers (except the central pair) tipped with 

 buffy brown. In very young birds the underparts are more or less 

 tinged with "cinnamon-buff," most strongly on the flanks and crissum, 

 which fades out to dull white in older birds ; there is much individual 

 variation in the amount and distribution of the grayish brown spots 



