32 New Swallow from Western United States. 



claw, 13.7. The folded wing, in the recently-killed specimen, extended 

 13 mm. beyond the tail. Top of head parrot green. Nape with a 

 narrow collar of Indian purple. Whole of back bottle green, faintly 

 glossed with violet when viewed in a certain light. Rump and upper 

 tail-coverts, violet, shaded with plum-purple. Wing and tail quills, 

 black, strongly glossed with indigo above, their under surfaces slate- 

 gray; wing-coverts violet, edged with parrot green. Two white patches 

 on the rump, one on each side; these, in life, are brought close 

 together so as to form an apparently continuous white band across the 

 rump. Under surface all white, except the flight-feathers, this extend 

 ing to the hind neck and ear-coverts. Iris brown. Bill, brownish black. 

 Feet, dark brown; claws, black. 



Adult female. Similar to the male, but smaller, with color much 

 duller, the white of ear-coverts and hind neck much mixed with brown 

 ish gray. 



Young. Similar to the same stage of Tachycineta bicolor (Vieillot) 

 but with feathers of lower parts grayish beneath the surface; easily dis 

 tinguished by its smaller bill. 



Comparison. Adult male, No. 143,516, U. S. National Museum collec 

 tion, taken on Mt. Popocatepetl, Mexico, February 23, 1893, by E. W. 

 Nelson, a typical example of Tachycineta thalassina (Swainson), measures 

 as follows: wing, 127 mm.; tail, 58; exposed culmen, 5.6; tarsus, 11. 

 middle toe with claw, 15. The whole back is of a color intermediate 

 between -Indian purple and violet, changing to green if viewed in a 

 certain light. The rump and upper tail-coverts are bottle green. 



Geographic range. Western United States, from the eastern base of 

 the Rocky Mountains to the Pacific, north to British Columbia and 

 Alaska, (breeding throughout this range) south, in winter, to Guate 

 mala and Costa Rica. 



Remarks. Breeding birds of the present form from Arizona and 

 northern Mexico suggest by larger size and occasional green feathers 

 in the rump and upper tail-coverts but by no means prove intergrada- 

 tion with Tachycineta thalassina. I arn indebted to Dr. Louis B. Bishop 

 for specimens collected by him on the Yukon River, in July, 1899. 

 These are small, an adult male measuring: Wing, 112 mm.; exposed 

 culmen, 5. 



