way related. The striking resemblance which their eggs showed, however, sug- 

 gested an affinity which was later perfectly confirmed by anatomists and 

 embryologists. 



If we walk in the woods in June and happen to flush a night-hawk from the 

 ground the most careful scrutiny of the place where the bird rose will often fail 

 to reveal to our sight what at last our fingers detect — two eggs — their shells 

 imbued with the colors of the forest floor. I have led persons to a spot on a beach 

 of shells and sand, told them that there were twenty-one good-sized eggs within a 

 radius of fifteen feet and seen them utterly baffled. The olive-gray, blotched shell 

 of a tern's egg rests among dark pebbles, or more often upon a wisp of seaweed, 

 into whose irregularities the hues of the eggs melt and mingle perfectly. The 

 Black Skimmer, that most interesting bird of our coast, lays its eggs upon the 

 bare sand among, or sometimes in, the large clam shells which the storms throw 

 up in windrows. Against man's systematic search their wonderful assimilative 

 coloring is of course often useless, but sharp as is the eye of passing crow or 

 beach-patroling bear, the eggs to them would appear but bits of sand and shadow. 



And thus we might go on with many other examples of protection derived 

 from the piginent on the shells — protection which in a hundred instances might 

 prove futile, but which in the great summing up and balancing of Nature's profit 

 and loss is of inestimable value to the race. 



The color of the eggs have been carefully examined with the stereoscope and 

 are found to consist, chemically, of seven pigments — a brownish red, two delicate 

 blues, two clear yellows, a peculiar brown hue, while the seventh is a rather indefi- 

 nite shade known as lichenixanthioe, most interesting of all as being identical 

 with a color substance common in plants and especially in lichens and fungi. These 

 substances somewhat resemble those found in the blood and the bile. They are 

 deposited on the shell while the egg is passing down the oviduct, and it is to the 

 circular or erratic motion of the egg that the curious scrawls and blotches upon 

 some eggs are due. 



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