SAN LUCAS SWALLOW 383 



The range as outlined is for the entire species, which has been 

 separated into three subspecies. The typical race, known as the 

 Mexican violet-gi'een swallow {Tachycineta thdlussina thalassina) ^ is 

 confined to the Mexican tableland ; the northern violet-green swallow 

 {T. t. lepida) .occupies all the balance of the range except the Cape 

 district of Baja California, which is occupied by the San Lucas 

 swallow {T. t. hrachyptera) . 



Spring rnigration. — Early dates of spring arrival are: New Mex- 

 ico — Silver City, April 17. Colorado — Boulder, April 22. Wyoming 

 — Yellowstone Park, May 11. Montana — Anaconda, May 6. Alberta 

 — Red Deer, May 7, Arizona — Tombstone, February 18. California — 

 Los Angeles, February 19. Oregon — Portland, March 7. Washing- 

 ton — Tacoma, March 9. British Columbia — Okanagan Landing, 

 JMarch 6. Alaska — Fairbanks, May 8. 



Fall migration. — Late dates of fall departure are : Alaska — Thomas 

 Bay, August 22. British Columbia — Okanagan Landing, October 15. 

 Washington — Seattle, October 19. Oregon — Portland, October 7. 

 California — Kernville, October 28. Montana — St. Marys Lake, 

 August 10. Wyoming — Yellowstone Park, August 18. Colorado — 

 Boulder, September 9. New Mexico — Chloride, September 23. Ari- 

 zona — San Francisco Mountain, September 28. 



Casual records. — A specimen was taken at South Kenwood in the 

 Calumet region, near Chicago, 111., ,on May 4, 1897. In Alaska, two 

 specimens were obtained on St. Paul Island on August 22, 1914, and 

 one in immature plumage was taken at Point Barrow on August 26, 

 1929. 



Egg dates. — California: 31 records. May 1 to July 1; 15 records, 

 May 25 to June 11, indicating the height of the season. 



Baja California : 3 records. May 1 to June 16. 



Oregon : 19 records. May 27 to July 5 ; 9 records, June 4 to 17. 



TACHYCINETA THALASSINA BRACHYPTERA Brewster 



SAN LUCAS SWALLOW 



HABITS 



The violet-green swallow of the southern half of Lower California 

 was named and described by William Brewster (1902) as follows: 



Similar to T. lepida Mearns, but with the wing decidedly and apparently 

 constantly shorter. * * * The Violet-green Swallow of the Cape Region 

 furnishes an interesting illustration of the recognized fact that isolated, non- 

 migratory birds are given to having shorter wings than those which regularly 

 perform extended journeys, for in respect to the length of the wing it is almost 

 if not quite as much smaller than the form which breeds in the regions 

 further to the northward (i. e. California, Oregon, Washington, and British 

 Columbia) as the latter is smaller than true thalassina of the Mexican table- 

 land still further to the southward. * • * 



