58 LOONS. 



Sept. 3 to Oct. 28 ; a few summer. Cambridge, T. V. in Apl. ; very common 

 Sept. to Nov. ; breeds in one locality. 



Nest, a mass of water-soaked, decaying vegetation, sometimes' built up 

 from the bottom in shallow water, sometimes floating among rushes in a slough, 

 when it is generally attached to its surroundings. Eggs, four to eight, dull 

 white, more or less soiled or stained, 1'74 x 1-19. 



This is probably the best known of our Grebes, and is the one which 

 most frequently tempts the shot of would-be sportsmen. Its common 

 names may stand as an expression of its aquatic powers. It dives 

 head foremost, or sinks slowly beneath the water. Like other Grebes, 

 it can swim easily and for an indefinite period with only its bill above 

 the water, and its sometimes mysterious and apparently complete dis- 

 appearance is explained by this habit. 



FAMILY URINATORIDJE. LOONS. 



A family containing only five species, inhabiting the northern half 

 of the northern hemisphere. The Loons are scarcely less aquatic than 

 the Grebes, and are their equals as divers and swimmers. They visit 

 the land only to nest, when their clumsy progress is assisted by the 

 use of bill and wings. Their food consists of fish, which they procure 

 by diving, progressing when under water by aid of the feet alone. 



KEY TO THE SPECIES. 



A. Throat black. 



a. Head black 7. LOON. 



b. Head ashy 9. BLACK-THROATED LOON. 



B. Throat gray, foreneck chestnut 11. KED-THROATED LOON. 



C. Throat white or whitish ; back fuscous, margined with grayish. 



a. Wing over 13'00 ; base of bill to anterior end of nostril '75 or over. 



7. LOON (Im.). 



b. Wing under 13'OG ; base of bill to anterior end of nostril less than *75. 



9. BLACK-THROATED LOON (Im.). 



D. Throat white or whitish ; back fuscous, spotted with white. 



11. EED-THROATED LOON (Im.). 



7. Urinator imber ( Gunn.}. LOON. (See Fig. 5, b.) Ad. in summer. 

 Upper parts, wings, tail, and neck black with bluish or greenish reflections ; 

 spaces on the throat and sides of the neck streaked with white ; back and 

 wings spotted and barred with white ; breast and belly white ; sides and a 

 band at the base of the under tail-coverts black spotted with white. Ad. in 

 winter and Im. Upper parts, wings, and tail blackish margined with grayish 

 not spotted with white ; under parts white ; throat sometimes washed with 

 grayish. L., 32-00 ; W., 14.00 ; Tar., 3'40 ; B., 2-80. 



Range. Breeds from northern Illinois, Minnesota, and northern New Eng- 

 land to the Arctic Circle ; winters from the southern limit of its breeding 

 range to the Gulf of Mexico. 



