40. Geothlypis macgillivrayi (Aud.) Baird. Macgillivray’s Warbler.—Two specimens collected at Tucson (♀ April 20, ♂ June 8). “I have not found it common in either Arizona or New Mexico.”
41. Geothlypis trichas (Linn.) Caban. Maryland Yellow-throat.—Mr. Stephens found this species “abundant along streams,” an experience at variance with that recorded by Mr. Henshaw, who met with it but twice while in Arizona.
The only specimen taken agrees closely with some examples from the Truckee River, Nevada, and differs from my eastern representatives, in having the upper parts yellowish-olive instead of olive-green; the crown-band much broader and creamy white in color; the wings and tail longer; the yellow beneath richer, and extending more over the abdomen. Mr. Ridgway has already called attention[[69]] to some of these differences which, as he now writes me, would be enough to warrant the varietal separation of the western bird, were it not that specimens from both sections of the country occasionally vary in such a manner as to invalidate any characters that could at present be proposed. With the acquisition of better series, however, it is probable that the representatives of two regions, as yet undefined, will be found to present sufficiently constant characteristics to deserve distinctive names.
219, ♂ ad., Cienega Station, April 17. Length, 5.40; extent, 6.90; wing, 2.16; tail, 2.40; culmen, .55. “Iris brown; bill black, bluish beneath; legs pale brown.”
42. Icteria virens longicauda (Lawr.) Coues. Long-tailed Chat.—This bird was observed only in the vicinity of Tucson. The first specimen was taken April 30, and it soon afterwards became abundant.
310, ♂ ad., Tucson, April 30. Length, 7.50; extent, 9.40; wing, 3.12; tail, 3.52. “Bill and legs black.”
318, ♂ ad., Tucson, May 3. Length, 7.70; extent, 9.60; wing, 3.05; tail, 3.61.
335, ♂ ad., Tucson, May 5. Length, 7.30; extent, 9.70; wing, 3.12; tail, 3.45.
521, ♂ ad., Tucson, June 11. Length, 7.10; extent, 9.40; wing, 3.15; tail, 3.36.
43. Myiodioctes pusillus pileolatus (Pall.) Ridgw. Pileolated Warbler.