I06 BIRDS OF COLORADO. 
latter part of March, two or three weeks before the other varieties 
leave. Works upward as the snow leaves, and by the middle 
of June has left the region below 8,000 feet. Breeds abund- 
antly from the upper limit of shrubs to 1,000 feet below timber- 
line, and less commonly down to 8,500, and occasionally at 
7,000 feet. In October descends to lower valleys and soon 
leaves the county. D. D. Stone found fresh eggs from June 8 
to July 18 at 10,000 feet in Gunnrson County. (O. & O. IX. 
1884, 20.) Common on the plains during spring and fall migra- 
tion, remaining in the spring usually to the first of May, and 
rarely as late as June i. Capt. P. M. Thorne took it as far east 
as Fort Tyon. 
570a. Junco phaeonotus dorsalis. Red-backed Junco. 
Migratory; rare. The only record for Colorado is that of 
Chas. F. Morrison who says that they were abundant during 
the spring of 1887 at Fort Lewis in the extreme southwestern 
corner of Colorado. (O. & O. XV. 1890, 36.) This is the resi- 
dent and abundant form just south of the Colorado line and it 
would be strange if some did not enter the State. It has been 
entered above as migratory according to the record, but if it 
occurs as anything more than an accidental visitant, it must 
breed. 
573. Amphispiza bilineata. Black-throated Sparrow. 
Summer resident; not uncommon, locally. A southern 
and western species barely reaching to Colorado and found only 
in the southwestern portion. Abundant a little south of Colo- 
rado in Arizona. The only record east of the range and 
probably accidental, is one taken by C. E. Aiken, July 26, 
1872, in a mountain park near Canon City. 
574a. Amphispiza belli nevadensis. Sage Sparrow. 
Summer resident; abundant. Quite common on the sage- 
brush plains of western and southwestern Colorado. Comes 
east as far as San Luis Park, where Henshaw found it not 
uncommon up to 8,000 feet. 
581. Melospiza fasciata. Song Sparrow. 
Migratory; rare. Among five Song Sparrows taken by 
Capt. P. M. Thorne at Fort Lyon, and now in the Field Colum- 
bian Museum at Chicago, is one typical fasciata^ the other four 
being montana. Fasciata is the common form found through- 
out Kansas and Nebraska, and in view of the above record it is 
probable that a few migrate across the plains of the extreme 
eastern Colorado and may not unlikely breed in northeastern 
Colorado. 
