Nothing seems to have been published on the nest and eggs of the Alaska yellow warbler, nor on its habits, all of which probably do not differ materially from those of the species elsewhere in similar environment. DENDROICA PETECHIA MORCOMI (Coale) ROCKY MOUNTAIN YELLOW WARBLER HABITS This is another race that was described many years ago by H. K. Coale (1887) but has only recently been accepted by the A. O. U. Coale gave it its scientific name in honor of J. Frean Morcom and called it the western yellow warbler. The following remarks by Dickey and van Rossem (1938) tell the story very well: The race of yellow warbler summering in the Great Basin and Rocky Mountain regions of the United States of late years has been generally overlooked and has been synonymized commonly with _aestiva_ or, in part, with _brewsteri_. Although not a well differentiated form, its characters are readily apparent in series, and there is no reason why it should not be accorded equal standing with the races currently recognized. The underparts of the males are heavily marked, and in this respect _morcomi_ is not distinguishable from _aestiva_. Dorsally, however, _morcomi_ is darker and less yellowish green, particularly on the interscapular region. The females are, age for age, more buffy (less yellowish) below and darker and more grayish above than the females of _aestiva_. In comparison with _brewsteri_, _morcomi_ (particularly the bill) is larger, and the males are more heavily streaked below. The range of _morcomi_ is the Rocky Mountain region of the United States, north to Wyoming and Idaho, west to the eastern slope of the Sierra Nevada, and south (in the western part of its range) to Mammoth, Mono County, California. We have not seen material from the southern Rocky Mountains; so we cannot state the southern limits in that region. They call it a "common spring and fall migrant and winter visitant in the lowlands," of El Salvador. "Dates of arrival and departure are August 1 and April 9."