542 BULLETIN 203, UNITED STATES NATIONAL MUSEUM 



30. Wyoming — Laramie, October 15 (average of 7 years, September 

 17). Utah — Boxelder County, September 19. Colorado — Weldon, 

 October 20. Arizona — Keams Canyon, October 12. New Mexico — 

 Apache, October 12. Saskatchewan — Last Mountain Lake, August 25. 

 Manitoba — Aweme, September 9. Oklahoma — Cimarron County, 

 September 24. Texas — El Paso, October 8. Mexico — Sonora, 

 Cajon Bonito Creek, September 28. 



Early dates of fall arrival are : Utah — Salt Lake City, August 10. 

 Arizona — Tucson, August 6. New Mexico — Apache, August 3. Okla- 

 homa — Cimarron County, August 16. Texas — El Paso County, 

 August 21. Mexico — Sonora, Cerro Gallardo, August 14. Guate- 

 mala — Dueilas, September 17. Costa Rica — San Jose, September 25. 



Egg dates. — California: 39 records, May 2 to July 7; 21 records, 

 June 2 to 20, indicating the height of the season. 



Washington: 42 records, May 29 to June 22; 23 records, June 1 

 to 10 (Harris) . 



OPORORNIS TOLMIEI MONTICOLA Phillips 

 SOUTHERN MacGILLIVRAY'S WARBLER 



This race was named by Dr. Allan R. Phillips (1947) and described 

 as having the tail the "relatively longest" of the species; the "color 

 dull, differing from 0. t. tolmiei in darker and grayer (less yellowish) 

 green upper parts and paler and greener (less orange) yellow under 

 parts. The difference in color of the under parts is less constant in 

 fall females of unknown age, perhaps due to variation with age and 

 to erroneous sexing of some young birds." 



He says that it breeds "in dense deciduous brush of the Canadian 

 Zone from southeastern Oregon (Steens and Mahogany Mts.) and 

 southwestern Wyoming (Ft. Bridger and Steamboat Mt.) south to 

 central Arizona (White and San Francisco Mts.) and central New 

 Mexico (Alto)." 



It evidently winters in Mexico and Guatemala. 



GEOTHLYPSIS TRICHAS BRACHroACTYLA (Swainson) 

 GEOTHLYPIS TRICHAS TRICHAS (Linnaeus) 



NORTHERN AND MARYLAND YELLOWTHROATS 



CONTEIBUTED BY AXfRED QxTO GkOSS 



Plates 66-68 



HABITS 



While the following account applies primarily to the northern yel- 

 lowthroat Geothlypsis trichas hrachidactyla^ for practical reasons it 

 also includes the Maryland yellowthroat Geothlypsis trichas trichas^ as 



