390 Cameron, Stoainson's Hawk in Montana. buly 



Third Male Plumage. 



My hawk Mas unfortunately lost in 1910, which prevents me 

 from proving absolutely from a captive specimen that the follow- 

 ing conclusions regarding the third dress assumed, are correct. 

 Nevertheless, 1 believe that I can present a fairly accurate account 

 of the subsequent plumage changes in this species, based upon a 

 study of thirty skins and hundreds of wild birds. It must always 

 be recollected that, as some individuals differ remarkably in plum- 

 age front the congeners of the same age. allowance has to he made 

 for these dissimilarities. For example, in both sexes the chief 

 second plumage variation consists, apparently in the retention 

 or extinction of the spots on the underparts which form so con- 

 spicuous a feature in all birds of the year. In the third male 

 plumage the whole of the upper parts are light umber brown 

 with the head of a darker shade. Many feathers of the hack ami 

 scapulars are chestnut-edged, but the white margins of the second 

 plumage have disappeared. The primaries arc brownish-black 

 above becoming ashy, or pale slate, towards their bases on the inner 

 webs, attd slate color beneath, gradually blackening near the tips. 

 The entire upper breast is bright cinnamon with a purplish bloom, 

 and it is in this plumage that the white throat first appears, in 

 strong contrast to the cinnamon upper breast anil sooty brown 

 head. In three examples before me this white patch measures 

 two and a half inches long by one and a half inches wide. The 

 ventral surface and lining of the wings are buffy white, slightly 

 flecked or broadly splashed (according to the specimen) with a 

 paler tint of the breast color. The newly-grown light slate tail- 

 feathers have eight dark bars, and are a still paler shade of slate 

 below, but fade to brown before the next moult on the exposed 

 parts. The two upper rectrices always turn more or less brown 

 except at their bases which are protected by the secondaries in the 

 folded wing. If the former are raised, the original slate-colored 

 tail is disclosed. 



