338 BIRDS OF THE ROCKIES 



612. Cliff-swallow. PETROCHELIDON LUNIFRONS. Abun- 

 dant summer resident ; breeds everywhere from plains to 

 10,000 feet ; nests on cliffs and beneath eaves. 



613. Barn swallow. HIRUNDO ERYTHROGASTER. Com- 

 mon summer resident ; breeds from plains to 10,000 feet. 



6 14. Tree swallow. TACHYCINETA BICOLOR. Summer 

 resident ; not uncommon ; breeds occasionally on the 

 plains; more frequently in mountains up to 10,000 

 feet. 



61 5. Violet-green swallow. TACHYCINETA THALASSINA. 

 Summer resident ; abundant locally ; a few breed on 

 plains ; more commonly from 6,000 to 10,500 feet. 



616. Bank swallow. CLIVICOLA RIPARIA. Rare sum- 

 mer resident ; rarest Colorado swallow ; from plains to 

 foothills. 



61 7. Rough-winged swallow. STELGIDOPTERYX SERRI- 

 PENNIS. Summer resident ; not uncommon ; breeds below 

 7,500 feet. 



618. Bohemian waxwing. AMPELIS GARRULUS. Winter 

 resident ; not uncommon ; breeds north of the United 

 States. 



6 19- Cedar waxwing. AMPELIS CEDRORUM. Resident ; 

 not common ; breeds from plains to about 9,000 feet. 



621. Northern shrike. LANIUS BOREALIS. Common win- 

 ter resident; on its return from the North in October it 

 first appears above timber-line, then descends to the 

 plains. 



622a. White-rumped shrike. LANIUS LUDOVICIANUS EX- 

 CUBITORIDES. Common summer resident; breeds mostly 

 on the plains; sometimes in mountains up to 9,500 

 feet. 



