164 FRANCIS H. HERRICK 



for the gay and attractive colors which so many of them display 

 to man's great delight, if not to their own. He divided birds 

 into two groups, based solely upon whether the eggs, young, 

 and sitting parent, — that is the contents of the nest, — were 

 exposed or hidden from view. In the first division we should 

 find those species which canopy their nests or frequent dark 

 or cavernous places of any kind, while the second would em- 

 brace all which sit in the open, like a nighthawk, or which build 

 nests open from above, as in by far the greater number of modern 

 birds. Assuming that nesting habit was strictly correlated with 

 structure, and was more stable than color, he inferred that all 

 such species as the parrots, toucans, and kingfishers, which are 

 known to be equally brilliant in both sexes, the intensity and 

 equality of color was due to the habit of concealing their nests 

 or eggs. 



By nesting in hidden places both sexes of all such birds were 

 placed on an equality, so far as protection during reproduction 

 was concerned, so that sexual selection and other causes of 

 specific change were allowed to act unchecked, whether in the 

 production of bright colors or conspicuous markings. Female 

 birds, on the other hand, which had brilliant mates and built 

 open nests, were almost always obscure in the coloring of their 

 upper or exposed parts. The fact that both classes of nests 

 occur in such birds as the flycatchers, which are dull in either 

 sex, was dismissed by Mr. Wallace with the remark that such 

 coloring merely served to protect the parents at other times 

 than when engaged in reproduction, the structure of the nest 

 being dependent upon the needs of the offspring. 



Mr. Wallace was certainly right in assuming that coverings 

 of the nest in the form of canopies or shields serve more or less 

 effectively to protect its contents, but in error in limiting the 

 needed protection, as he seems to do, to concealment effected 

 in these ways. Protection indeed, in some measure, there must 

 be, but aside from every other question involved, it can be shown 

 that sharpened instincts are frequently a greater asset in secur- 

 ing this protection than anything connected with the nest itself. 



Without entering the labyrinths of the color question, we 

 shall endeavor to show in the following section how protection 

 is actually secured during the nesting period by certain species, 

 regardless of color in the adult or of the open or closed nature 



