390 COLYMBID^ : LOONS. 



breed ; " Allen marks it as a rare autumn and winter 

 visitant ; and Mr. Harold Herrick gives it as of Grand 

 Menan. In a dilemma like this (and there are several 

 such among our water birds) it is useless to deny a 

 moral certainty merely because the circumstantial evi- 

 dence is not absolutely conclusive, or because we lack a 

 "modern instance." 



RED-THROATED DIVER. 



COLYMBUS SEI'TENTRIONALIS Z. 



Chars. Blackish ; below white, dark along the sides and on the 

 vent and crissuni ; most of head and fore neck bluish-gray, the 

 throat with a large chestnut patch ; hind neck sharply streaked 

 with white on a blackish ground ; bill black. Young have not 

 these marks on the head and neck, but a profusion of small, 

 sharp, circular or oval white spots on the back. Size of the last, 

 or rather less. 



A common winter visitant along the whole coast, 

 arriving from the north in September or October, and 

 remaining until May. It is most abundant during the 

 migrations in fall and spring, and has even been seen in 

 Southern New England in June; but it is not ascer- 

 tained to breed within our limits. According to May- 

 nard, it is the most numerous representative of the 

 family during autumn and winter. Mr. Deane speaks 

 of a perfect albino in his possession, which was shot in 

 Salem harbor, Mass. Individuals in perfect plumage, 

 with the red throat, are rare in comparison with the 

 numbers seen in the spotted plumage of the young. 



