RIVOLI'S HUMMINGBIRD 319 



The range above outlined is for the entire species, but a southern 

 subspecies {A. s. nigrior), apparently resident in the southern part 

 of the range, is now recognized. 



Winter range. — In winter these swifts are found north to Cali- 

 fornia (Alum Rock Canyon, Santa Clara County, Redlands, Indio, and 

 Salton Sea) ; casually central Arizona (Big Sandy Creek and 

 Phoenix); and southwestern New Mexico (15 miles southwest of 

 Hachita and Chloride) . From these northern limits the winter range 

 extends southward, probably to Guatemala and El Salvador. 



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

 ico — Chloride, March 6. Colorado — Colorado Springs, March 20; 

 Durango, April 4; Palisades, April 25. Wyoming — Laramie, April 

 24; Midwest, April 28. South Dakota — Sioux National Forest, May 

 12. Montana — Billings, April 23. Arizona — Tucson, March 9 ; Par- 

 adise, March 14; Grand Canyon, March 25. Utah — Salt Lake, May 

 1. Washington — Everett, May 10. 



Fall migration. — ^Late dates of fall departure are : Utah — ^Willard, 

 September 4. Arizona — Grand Canyon, October 6. South Dakota — 

 Hot Springs, September 9. Wyoming — Laramie, September 9. Col- 

 orado — Boulder, October 2. 



Casual records. — A specimen of this species was captured alive at 

 Hillsdale, Mich., in August 1926; and another was obtained at Hot 

 Springs National Park, Ark., on May 4, 1935. 



Egg dates. — California : 86 records, May 8 to June 21 ; 43 records, 

 May 21 to June 3, indicating the height of the season. 



Family TROCHILIDAE: Hummingbirds 



EUGENES FULGENS (Swainson) 



RIVOLI'S HUMMINGBIRD 



Plates 49, 50 



HABITS 



This fine, large hummingbird is the largest of our North American 

 hummingbirds, though the blue-throated hummingbird closely ap- 

 proaches it in size, the two appearing about equally large as seen in 

 life. It is also one of the handsomest, although not so brilliantly 

 colored as some of the smaller species. In the male the crown is a 

 rich metallic violet-blue, and the throat a brilliant emerald-green, 

 abruptly contrasted with the glossy -black breast and the bronzy green 

 of the back ; this color pattern is so arranged that every change in the 

 bird's position brings a different color into view. 



It is mainly a Central American species, ranging as far south as 

 Nicaragua, through the tablelands of Guatemala and Mexico, and 



