176 MIGRANTS AND WINTER RESIDENTS. 



found in the markets and restaurants all through the 

 wmter." (Avifauna Columbiana.) 



American Herring Gull; Sea Gull: Lams argentattis 

 sinitlisoniaiiiis. 



Back and wings pearl-gray, the wings with black mark- 

 ings; rest of plumage white. Length 2 feet. October to 

 March. Common. 



Ring-billed Gull: Lanis delawarensis. 



Back and wings pearl-gray; wings marked with black and 

 white; rest of plumage white; bill greenish-yellow, encircled 

 near the end with a broad black band. Length 20 inches. 

 February to April 5; October to November. Very common. 



Bonaparte's Gull: Lams Philadelphia. 



Much smaller than the preceding. In summer, head and 

 upper neck dark slate color; back and wings pearl-gray; 

 rest of plumage white. Immature birds and adults in fall 

 without black head. Length 14 inches. April to May 5; 

 October to November. Common. 



Black Tern: LLydrochelidon nigra snrinamensis . 



In summer, head, neck and under parts black; back, 

 wings and tail slate color; bill and feet black. In winter, 

 forehead and under parts white. Length 10 inches. Some- 

 times common in August and September. 



Loon: Gavia iinbcr. 



Head and neck dark bluish-green, patches of mottled 

 white on throat and sides of neck; upper parts and sides 

 glossy black, conspicuously spotted with white; under parts 

 white. Length 2^ feet. September to April 25. Common. 



