Jan., 1912 SOME BIRDS OF SOUTHWESTERN MONTANA 31 Cinclus mexicanus unicolor. Dipper. Permanent resident along mountain streams. Not very common in this region, probably because the streams are mostly small and many of them kept continually muddy by placer mining. Though a per- manent resident a noticeable migration takes place in March and October, when individuals may be found far from their usual haunts, occasionally in the valleys, and often swimming on the surface of mountain lakes. They winter commonly along Warm Springs Creek, near Anaconda and along the Boulder River, in Jefferson County, places where to my knowledge they are never found in summer. 0reoscoptes montanus. Sage Thrasher. Seen in the sage-brush near Silver Bow, May 21, 1910. Dumetella carolinens/s. Catbird. Summer resident in the valleys. Migration date May 28, 1911. Salpinctes obsoletus obsoletus. Rock Wren. Summer resident in suitable local- ities up to 6,000 feet. Migrations appear to be irregular. In 1910 a single indi- vidual was seen on April 13 and the species became common on May 1. In 1911 none were seen until May 2,0. Fall dates ire September 8, 1909, and September 18, 1910. The record for September 8, 1909, is that of a pair of birds seen in slide rock, near the head of Ten-mile Creek, Deer Lodge County, at an elevation of 9,500 feet, more than 3,000 feet higher than the species usually occurs. Nannus hiemalis pacificus. Western Winter Wren. Seen in German Gulch. Silver Bow County, on May 23 and 24, 1910, and one secured on the latter date. Another seen on Gold Creek, Powell County, August 15, 1910. Tehnatodytes palustris plesius.. Western Marsh Wren. Seen near Gold Creek, Powell Connty, September 21, 1910, and near Anaconda, April 18, 1911. Speci- mens were secured on both dates and referred to this subspecies by Dr. Bishop, though one of the Anaconda specimens was not typical but like T. p. ?'/iacus in some respects. Certhia familiaris montana. Rocky Mountain Creeper. Summer resident of spruce forests in the mountains. Migration dates are April 26, 1910, October 14, 1909, and October 9, 1910. Sitta carolinensis nelsoni. Rocky Mountain Nuthatch. Summer resident in the mountains but not common. Seen most frequently at high elevation in white- bark pine forests in September and October. Sitta canadensis. Red-breasted Nuthatch. Summer resident in the yellow pine forests of Powell County. A migrant elsewhere in the region. Migration dates are April 18, 1910, and October 2, 1909. Penthestes atricapillus septentrionaHs. Long-tailed Chickadee. Common per- manent resident of the willow thickets and cottonwood groves of the valleys. Penthestes gambeli gambeli. Mountain Chickadee. Common permanent resi- dent of the mountains. Regulus satrapa olivaceus. Western Golden-crowned Kinglet. Summer res- ident of spruce forests inthe mouutains. Most abundant in migrations. According to the Check-List, ]7. s. satrapa should be the breeding form in Montana. Perhaps this is the case, for though I have taken several birds referable to IY. s. olivaceus, they have all been fall migrants and not breeding birds. Regulus calendula calendula. Ruby-crowned Kinglet. Abundant summer resi- dent of fir forests in the mountains. Migration dates are March 31, 1910 (an unusually early date), April. 20, 1911, September 26, 1909, and September 20, 1910. There appear to be two forms of kinglet in this region, differing from each other in habitat and song but not perceptibly in plumage or measurements. One form is only a migrant, arriving a week or two earlier than the other, inhabiting willow
