Water Fowl 



On the other hand, the commonest species 

 of water birds are much more equally distrib- 

 uted among all the orders, and the variety of 

 types therein is very extreme. This affords a 

 most interesting diversity. About nine-tenths 

 of all the land birds which the average student 

 will find are in the song group ; which are 

 classified, to be sure, into about twenty fam- 

 ilies ; yet the general type of all of them is so 

 uniform that the observer would hardly consider 

 it incongruous if they had been arranged in 

 two instead of twenty families. Thrushes, 

 finches, tanagers, waxwings, and blackbirds, 

 only differ in subordinate details ; and certain- 

 ly warblers, vireos, and flycatchers are com- 

 paratively uniform in general figure. 



But notice the remarkable gradation, not in 

 size only, but especially in the fundamental 

 structural form of the various groups of water 

 fowl, as represented by the sandpiper, oyster- 

 catcher, woodcock, phalarope, avocet, rail, 

 curlew, heron, peUcan, flamingo, swan, duck, 

 penguin, cormorant, snake-bird, loon, gull, guil- 

 lemot, puffin, grebe, petrel, albatross — a variety 

 of types consistent with their extreme diversity 

 of life, as wading, swimming, diving, and aerial 

 water fowl. When all the varieties of figure 



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