156 PACIFIC COAST AVIFAUNA No. 14 



Tile OL'ciuTfiK-e ;it (li-cat F'alls. eited above, is the only record which may 

 indicate the date of arrival. The Brown Thrasher nests in June (Cameron, 

 1908a, p. 52) ; a nest was found between Ports Union and Benton, June 22, 1860 

 (Cooi)er, 1869b, p. 296). 



:!0:i. Salpinctes obsoletus obsoletus (Say) 



Rock Wr?:x 



A eoinnion suiiiiiicr resident througliout the state. Breeds in the Upper 

 Sonoran and Transition zones, in badlands and about the sides of prairie buttes 

 in the prairie region, and in rocky situations about the foothills of the mountains 

 in the western half of the state. Prefers arid rocks in regions that are more or 

 less treeless. Occurs rarely in the Boreal zone in migration. Reported by nearl.v 

 all observers. 



The migrations take jdace in Jlay and September. The species ai-rives about 

 May 15 in Custer and Dawson counties (Cameron, 19()8a, p 53). Other dates 

 are: Divide Creek, Silver Bow County, one seen April 13, 1910. not common til) 

 May 1 (Saunders, 1914a, p 31) ; Traill Creek, Park County, May 14, 1909; Ana- 

 conda, May 20, 1911; Rattlesnake Butte, Teton County, May 27, 1912. Fall 

 dates are: Deer Lodge County, September 8, 1909, two birds observed in rocks 

 above timberline at 9000 feet; Willow Creek, Powell County, September 18, 1910. 



There are several records of the finding of the nest of the Rock Wren in 

 Montana, but none with definite date of nesting. A nest was found with eight 

 eggs at Fort Benton about June 25, 1860 (Cooper, 1869b, p. 297). Young 

 are full-feathered by July 3 (Cameron, 1908a, \i. 53). I have observed young 

 out of the nest on Pish Creek, Silver Bow County, July 10. 1910. and on Wild 

 Horse Island, Flathead Lake, July 2, 1914. 



304. Thryothorus ludovicianus ludovicianus (Latham) 



C.vROLiNA Wren 

 Rare in the southeastern part of the state. Two obtaiued in May on tiie 

 divide between Powder and Tongue rivers, and one in May and two in August 

 at Lame Deer (Thorne, 1894, p. 218). Seen near Billings in 1918 (Thomas, MS). 



305. Troglodytes aedon parkmani Audubon 



Western HorsE Wren 



A common summer resident over most of the state. Breeds in the Transition 

 zone, in holes in trees, in groves of Cottonwood or yellow pines, or in bird boxes 

 and crevices of buildings about ranches and in towns. Rare in the southwestern 

 part of the state, where it is not reported from Jefferson, Silver Bow, Deer 

 Lodge or Powell counties, nor from the Big Hole Basin. It is rare, though 

 breeding, occasionally, near Stevensville. in the Bitterroot Valley (Baile.v, IMS). 

 In all other parts of the state observers rejiort it as common. 



S]iring migrations take i)lace in ila.v, but no data on fall migration are to 

 tie had. Exact dates are as follows: Sedan. Gallatin County. May 20, 1909: Cho 



