THE MOUNTAIN MOCKING-BIRD. 17 



breeding over nearl}' the whole area, but not very plentifully, 

 and always amid the desolation of the sage-brush plains. Nut- 

 tall had the good fortune to find the first nest reported, in what 

 is now western Wyoming. It was placed in a "wormwood" 

 bush, and "was made of small twigs and rough stalks, lined 

 with strips of bark and bison wool." 



In northern Nevada — the centre of their summer range — the 

 ardent males begin that eager rivalry which marks the approach 

 of the bi'eeding season, early in April, and the first eggs are 

 laid by the 20th, the nests having been begun a week earlier. 

 This date is also true northward to Oregon at least, and full 

 time is thus left for bringing out a second brood. As soon as 

 the laying begins, the males become perfectly silent, "their main 

 occupation being that of sentinel on guard for the approach of 

 an intruder." 



While a sage bush, or its prickly companion the greasewood, 

 is preferred by the mountain mocker, he also places his domi- 

 cile on other bushes and small trees, brush-heaps, or even on 

 the ground at the roots of a bush ; but always low down. It 

 is a large, rude structure, built of twigs and lined with fibrous 

 roots. A curious nest was noted by Henry Henshaw in his 

 report to Lieut. Wheeler, in charge of explorations and sur- 

 veys west of the 100th meridian. It was seen on June 22, at 

 the Alkali Lakes near Fort Garland, Colorado, when the 

 embryos were nearly ready to be hatched. This nest, a bulky 

 affair of twigs lined with grass, was placed in a low bush. 

 Eight or ten inches above it was a platform of twigs, which, 

 whatever may have been the oi^iginal intention, certainly served 

 as an admirable screen from the rays of an almost tropical sun. 

 It may possibly have been intended as the site of the nest, and 

 then, for some reason, abandoned for the one beneath. 



The four, rarely five, eggs average 1.02 by .71 of an inch, 

 and present little variation in any respect. In color they are 

 rather light greenish-blue, boldly and sharply marked all over, 

 but more thickly at the large end, with spots of burnt brown, 

 underneath which are a great number of smaller specks, points 

 and fjtint touches of a lighter brown, yellowish, purple and 

 lavender. It approaches some styles of mocking-birds' eggs. 



