May, 1914 BIRDS O1' NORTHERN MONTANA 139 in the mountains, nesting in willow thickets along streams in the Canadian zone. Migration date: May 30, 1912, on ?)upayer Creek. l?a?serella iliaca iliaoa. 1%x S?arrow. I observed a bird that was evi- dently of this subspecies in ?tannan Gulch on the Sun River, October 18, 1911. The bird was in a dense aspen thicket and approached to within three or four feet of me. Passerella iliaca schistacea. Slate-colored l?ox Sparrow. Rare summer resident in the mountain. s, nesting in dense willow thickets along streams. This is evidently close to the northern limit of the breeding range on this side of the continental divide. I observed the species most frequently on the Sun River and on Willow Creek, in northern Lewis and Clark County. Pipilo maculatus arcticus. Arctic Towhee. Common summer resident of Fig. 46. NEST AND EGGS OF WESTERN MEADOWLARK. willow thickets on the prairies. Migration date: May 12, 1912. Zamelodia melanocephala. Black-headed Grosbeak. Common summer resident of willow thickets on the prairies. Begins nesting the middle of June. Young are on the wing the latter half of July. Migration dat?: June 7, 1912. (See fig. 48.) l?asserina amoena. Lazuli Bunting. Summer resident. Not common,
but most frequent along the foothills of the mountains in the southern part of
the region. Calamogpi?a melanocory?. Lark Bunting. Summer resident on the prai- ries. Rare during my stay, but information indicates that here as well as elsewhere in Montana, these birds were very abundant in the year 1907.
