334 



COLYMBIDAE, LOONS. GEN. 311. 





of many feathers. Back spotted. Loons are large heavy birds with broad flattened 

 body and rather long siunous neck, abundant on the coasts and larger inland waters 

 of the Northern Hemisphere ; they are noted for their powers of diving, being able 

 to evade the shot from a gun by disappearing at the flash, and to swim many 

 fathoms under water. They are migratory, breeding in high latitudes, generally 

 dispersed further south in winter. They are prificocial, and lay two or three dark- 

 colored spotted eggs in a rude nest of rushes by the water's edge. The voice is 

 extremely loud, harsh and resonant. The 9 is smaller than the <? . There is but 

 one genus, with only three well-determined species. 



311. Genus COLYMBUS Linnaeus. 



Great Nortliern Diver, or Loon. Black; below from the breast white, 

 ■with dark touches on the sides and vent ; back with numerous square white 

 spots ; head and neck iridescent with violet and greeu, having a patch of 

 sharp white streaks on each side of the neck aod another on the throat ; 



bill black. Younsr : 

 dark gray above, 

 the feathers with 

 paler edges ; below 

 white from the bill, 

 the sides dusky ; 

 bill yellowish-green 

 and dusky. Length 

 2A-3 feet ; extent 

 about 4 ; wing about 

 14 inches ; tarsus 3 

 or more ; longest 

 toe and claw 4 or more ; bill 3 or less, at base 1 deep and J wide ; the 

 culmen, commissure and gonys all gently curved. N. Am., abundant; 

 the whole U. S. in winter. Wils., ix, 84, pi. 74, f. 3; Nutt., ii, 513; 



AuD., vii, 282, pi. 476; Lawe. in Ed., 888 torquatus. 



Var. ADAMSii. Yellotu-biUed Loon. Similar ; larger ; spots on the back larger, 

 not so nearly square ; gloss of the neck rather steel-blue, the white patches smaller, 

 but the individual streaks larger ; hill mostly yellowish-ivhite, nearly 4 long, higher 

 and comparatii'ely narrower at the base, the gape straight, the culmen and gonys 

 nearly so (fig. 213 shows the shape exactl}^ although intended for the common 

 species). Northwestern America, chiefly; England; Asia. Gray, Proc. Zool. 

 Soc. 1859, 167; Codes, Proc. Phila. Acad. 18G2, 227; Elliot, pi. C3. 



Black-throated Diver. Back and under parts mucli as in the last species ; 

 upper part of head, and hind neck, bluish-ash or hoaiy gray ; fore neck 

 purplish-black with a patch of white streaks, the dark color ending abruptly ; 

 bill black. The young resemble those of that species, but will bo known 

 by their inferior size. Length under 2J feet ; extent about 3 ; wing 

 13 or less ; tarsus 3 ; bill about 2J. N. Am. and N. Europe ; said to be 

 common and generally dispersed throughout the U. S. in winter, which is 

 contrary to my experience. Sw. and Rich., F. B.-A. ii, 47.5; Nutt., ii, 

 517; AuD., vii, 295, pi. 477; Lawr. in Bd., 888 aecticus. 



Fig. 213. Great Northern Diver. 



