552 CLASS AVES. 



Northern Diver, Lath. Col. Glacialis, L. Enl. 952. 

 Col. Immer, Gm. Wilson, Am. ix. y^^j 8. Naum. 

 m, f. 103. 



Of which the adult, two feet and a half long, has the 

 head and neck black, changing into green, with a 

 whitish collar ; the back is brownish black, dotted 

 with whitish, and beneath is white. The lower 

 mandible slightly bent toward the upper, has a ridge 

 underneath. The young, Col. Immer, Gm. Briss. 

 iv. X. 1, which comes more frequently to our fresh 

 waters, varies by more or less black on the neck, and 

 grey or brown on the back, which, with their small- 

 ness, has caused the species to be multiplied. 



The C. Immer, Gniel. The Imber Diver, Lath. 

 Penn. Br. Zool. t. 84. 



From these are to be distinguished, 



Slack -throated Diver, Edw. Col. Arcticus. L. Edw. 

 146. Naum. Sup. 30, f. 60, and the young 

 Enl. 914. 



Which is a little less, and has the upper part of the 

 neck ash, and the lower mandible straight, and with- 

 out a furrow. The young are very like the last 

 species. 



The Lesser Imber, Bewick ; and Newcastle Diver, 

 Lath. Hist. 



