in quiet water, while shorter ripple-lines also roll out in front of the bird's 

 breast. Seen in profile against the water, the duck's body hides a portion of 

 the perturbed and wavy surface extending from its further side, and tends to 

 'relieve' noticeably against it. But this 'relieving' Nature combats with the 

 bright 'secant' stripes, which, by their beautiful likeness to rolling wavelets, 

 with shine and shadow, go far toward 'merging' the duck's otherwise well 

 'obliterated' body into the troubled water beyond it. The peculiar ripples, 

 real and pictured, may still suggest a swimming bird, but just where the bird 

 really is — where alone the eye is led to expect it — there seems to be nothing, 

 but water, — ^for the wave-lines extend across its dim body. This is a very 

 important factor of disguise among ducks, particularly those that inhabit 

 quiet inland water. Among deep-sea ducks it is less common. But the 

 same system, sometimes elaborated, and including sharp transverse markings, 

 occurs on a few of the oceanic species. 



Another peculiar form of pattern, common to even more kinds of duck, 

 is a fine, black or gray vermiculation of the back or sides, as on Teals, Scaups, 

 Canvasbacks, Wood Ducks, and many others. Indeed, this pattern is al- 

 most universal among ducks, and there are comparatively few (these mostly 

 deep-sea kinds) that lack all trace of it. It serves as a generalized picturing 

 of shimmering water, fretted with broken shore-reflections, or ruffled into tiny 

 ripples by light breezes. Considering its prevalence among highly 'obliter- 

 ated' water birds, one can hardly doubt that such is its main function. On 

 some species which frequent shallow inland waters, like the Wood Duck and 

 the Hooded Merganser, the dusky vermiculation is exceedingly close and 

 delicate, over a ground-color of golden brown. In these cases it seems to 

 picture the sandy bottom seen through shallow water at the stream's or 

 pond's edge. As a rule, the vermiculated pattern occurs on the sides, and 

 its minuteness therefore fits it to match its wearer's more or less distant 

 watery background, with its ripples and reflections dwarfed and refined 

 by perspective. The much coarser wavy markings of some geese, though 

 they serve also the purpose of ground-, and grass-picturing, in conformity 



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