122 
BIR£)S of COLORADO. 
erii Colorado. The only one who has formally noted both forms 
is V. L. Kellogg, who reports finding both in Kstes Park during 
the summer. (Trans. Kans. Acad. Science, XII. 1889-90, 86.) 
A specimen taken at Fort Collins is a fair intermediate between 
the two forms. Not enough material has been collected to de- 
fine its range in Colorado. 
727a. Sitta carolinensis aculeata. Slender-billed Nut- 
hatch. 
Resident; common. This is the common form in Colo- 
rado occurring throughout the State from the foothills westward. 
Winters at the edge of the plains and in the foothills, less com- 
monly nearly to the pines. Breeds occasionally down to the 
plains, but commonly from about 7,500 feet to timber-line. Its 
upward movement occurs in April and it breeds the last of May 
and early in June. Returns to the lower regions in October. 
728. Sitta canadensis. Red-breasted Nuthatch. 
Resident; not uncommon. Migratory on the plains and 
resident in the mountains to about 8,000 feet, occasionally to 
10,000 feet. Less common than the Slender-billed or the Pygmy 
Nuthatches. Breeds in June. 
730. Sitta pygmaea. Pygmy Nuthatch. 
Resident; abundant. Comes east only to the edge of the 
plains and occurs there only in the winter. Descends from the 
mountains in December and remains through until February. 
By the first of March all have r«turned to the mountains. At 
the same time they are fully as abundant in the mountains, 
braving the severest cold to at least 8,000 feet. During the 
Slimmer they are most common from 7,000 to 10,000 feet and a 
few breed as low as 6,000 feet. The great bulk scarcely make 
any migration, even vertical. Begins to pair in April and laying 
begins the latter part of May. Probably two broods are often 
reared. 
733a. Parus inornatus griseus. Gray Titmouse. 
Resident; not common. Known only from southern Colo- 
rado, coming north to B 1 Paso County and east to the eastern 
foothills. It has been taken from 5,000 to 9,000 feet and is 
known to breed, but its breeding range is nOt yet definitely de- 
termined. It seems probable that it winters in the foothills 
and breeds from 5,000 to 8,000 feet. 
735a. Parus atricapillus septentrionalis. Tong-tailed 
Chickadee. 
Resident; not uncommon. Winters on the plains and 
in the foothills, occasionally up to 8,000 feet. Breeds in the 
