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COLYMBUS. 
drawn forward to give tlie stroke, and, with the 
thin edge of the tarsus, thus offers a very slight re- 
sistance. Tho food is entirely fish taken by diving. 
The number of species is limited, and they are 
confined chiefly to northern and temperate clmates. 
The generic characters of this form are, 
Gen. Colymbus, Linnceus. — Generic characters. 
— Bill long, straight, pointed, strong, tomia 
smooth, lower outline of mandible curved, but 
showing little or no angle ; nostrils basal, late- 
ral, linear ; wings short, accuminatcd, feathers 
in structure stiff, first and second quills longest ; 
tail short, rounded; legs placed far behind, tarsi 
much compressed, feet large, amply webbed, 
outer toe longest, nails broad and flat, hallux 
articulated inside the tarsus, lobe small. 
Types. — C.glacialis , arcticus, &c. — Europe, Asia, 
America. 
Note . — Habits peculiarly aquatic, maritime; breed 
inland ; a marked summer plumage, lost in 
winter. 
