LIFE HISTOEIES OF NORTH AMERICAN DIVING BIRDS. 35 



October 27. Wyoming: November 10. Missouri: September 22 to 

 November 2 (formerly). Kansas: September to November. North- 

 ern Arizona: September. Oregon: Fort Klamath, November 7. 

 Lower California: San Jose del Cabo, October 18. Jalisco: Ocot- 

 lan, September 28. 



Casual records. — Indiana: May 19 and November 5. AVisconsin: 

 Several spring specimens. Illinois : Lake Michigan, winter ( ? ) . 

 Michigan records are discredited. 



Egg dates. — North Dakota and South Dakota: 41 records, April 

 29 to July 23 ; 21 records, June 4 to 27. Colorado : 19 records. May 

 10 to July 20; 10 records, May 28 to July 6. California : 14 records, 

 April 22 to August 2; 7 records, June 8 to 19. Saskatchewan: 9 

 records, June 10 to 26 ; 5 records, June 13 to 22. Oregon and Wash- 

 ington : 9 records. May 3 to July 5 ; 5 records, June 1 to 12. Utah : 

 3 records, April 22, June 20 and July 2. 



COLYMBUS DOMINICUS BRACHYPTERUS Chapman. 



MEXICAN GREBE. 



HABITS. 



As this little tropical species, the smallest of the grebes, is the 

 only one of the North American grebes that I am not familiar with 

 in life, I must draw wholly from the observations of others for an 

 account of its life history. Unfortunately, published notes on its 

 habits are very scantj?^, so the story will be short and incomplete. 

 Prior to 1899 the San Domingo grebe {Golymlms dominicus) stood 

 on our Check List, as found in the West Indies, southern Texas, 

 Mexico, and Lower California, as well as in tropical South America. 

 But Frank M. Chapman (18996) discovered certain geographical 

 varieties of the species worthy of recognition in nomenclature and 

 separated it into three subspecies. His description separates the 

 Mexican form, which also ranges into Texas and Lower California, 

 from the West Indian bird under the name of hrachypteriis^ having 

 a much shorter wing and a smaller bill. This seems to be a well- 

 marked subspecies in which the characters are constant. 



Mr. Vernon Bailey (1902) observes: 



These tiny grebes are as common in tlie ponds of soxitliern Texas as the dab- 

 cliick in the North. In open water they bob on the little waves, and in quiet 

 pools where the willows overhang the banks swim and dive among the sedges 

 and pink water lilies. When not seeking food below the surface of the water 

 they usually keep close to some cover, and in the middle of the day if not 

 hidden in the sedges are found sitting close under the shore grass or in the 

 shade of a bush or low-hanging tree. 



Nesting. — Mr. Frank B. Armstrong, who has collected many sets 

 of eggs of this grebe near Brownsville, Texas, wrote to Major Ben- 



55916— 19— Bull. 107 4 



