VARIATIONS IX HYLOCICHLA USTULATA — BOND 375 



subspecifically distinct. To this race he gave the name Hylocichla 

 ustulata almae. The following year, Oberholser (1899, p. 23) divided 

 the russet-backed population of the Pacific coast into two forms. 

 Birds from California and interior Oregon were given the name 

 Hylocichla ustulata oedica, and the nominate form H. u. ustulata was 

 restricted to birds of the northwest coast region. 



The A.O.U. check-list connnittee (1899, pp. 127, 131) rejected the 

 first of these names and accepted the second. This acceptance, 

 however, w^as temporary; the committee (1908, p. 335) later rejected 

 both names so that neither appeared in the third edition of the A.O.U. 

 Check-List in 1910 nor in the foui'th edition in 1931. 



Fm-thcr investigations of these thrushes led to temporary acceptance 

 of almae as a valid name by the A.O.U. committee (1944, p. 457) but 

 it was dropped again at a later date (1953, pp. 360-361). 



In succeeding studies, Burleigh and Peters (1948, p. 118) separated 

 the breeding birds of Newfoundland and Nova Scotia under the name 

 clarescens, and Godfrey (1951, p. 173) described Hylocichla ustulata 

 incana for the breeding population found from eastern Alaska and 

 western ^Mackenzie south to northern British Columbia and northern 

 Alberta. These two forms were added in the fifth edition of the 

 A.O.U. Check-List (1957, pp. 439-440) to typical ustulata and swain- 

 soni of the two previous editions. 



Status of Proposed Names 



In considering the dorsal coloration of Swainson's thrush across 

 its entire breeding range in North America from Alaska to Newfound- 

 land and southward in the Rocky and Appalachian Mountains, two 

 distinct patterns are observable. The population from Alaska to the 

 southern Rockies is definitely grayish above with several seasonal 

 and sexual variations that approach the reddish olive of the eastern 

 group. There is a weak color cline in which birds from the southern 

 Rockies appear paler than birds from Yukon and Alaska, but I con- 

 sider this tendency too slight to warrant nomenclatural recognition. 

 Recently collected material from Idaho and eastern Washington are 

 practically indistinguishable from birds collected during the last few 

 years in northwestern Yukon. The type of almae from Nevada has 

 been considered as a representative of swainsoni, but critical exami- 

 nation shows it to be a somewhat atypical specimen of the western 

 population. At any rate, it is definitely a gray bird when compared 

 with specimens from the eastern population. A specmien from 

 Mountain City, Nev., is also definitely gray, as are specimens from 

 southern Idaho and northwestern Utah. For this reason, the bird 

 from Franklin Lake, Nev., described by Oberholser as almae will have 

 to be considered the type of the grayish western population and the 



