155 



Comparative Measurements. 



No. 146 is a full plumaged male shot in May.. 

 No. 173 is the young specimen described above. 



COLYMBUS TORQUATUS, Brunn. Loon. Northern Diver. 

 Summer visitant. Very common. Breeds. Arrives 

 about the middle of April. The eggs are laid about the 

 middle of June and sometimes later. Young are hatched 

 the first week in July. 



C. ARCTICUS, (?) Linn. Black-throated Diver. A speci- 

 men in immature plumage shot May 6th, 1858, agrees 

 very closely with Audubon's description of the young of 

 this species, but seems to be rather the young of C. tor- 

 quatus. I have never obtained an undoubted specimen 

 of C. arcticus. 



PODICEPS CORNUTUS, Lath. Horned Grebe. Spring and 

 Fall. Not common. 



PODYLIMBUS PODICEPS, Lawr. Water Witch. Spring and 

 fall. Common. It is possible that this species breeds 

 here, but I have never seen it in summer. 



