NESTS AND NEST-BUILDING IN BIRDS 165 



of the nest. Whatever conditions may have prevailed in the 

 past, it is easy to see that the facts of color and nesting habit 

 are too diverse and too complex for any such simple analysis. 

 Few species have yet been studied with sufficient care with 

 reference to all the factors involved, and no theory can have 

 any weight which does not consider all the elements of the 

 problem, and in particular the instincts of the adult in relation 

 to those of the young. 



A work on nests by Dixon '" contains much interesting matter 

 on the structure of nests as well as upon the nesting habits, but 

 little on the behavior of the builders. The author was a cor- 

 respondent of Mr. Wallace, supplied him with some of his facts, 

 and echoes his theories. His attitude on the problems of instinct 

 and intelligence in birds is apparent in his preface: If a " bird's 

 nest " were really " a most graphic mirror of a bird's mind," 

 as this writer asserts, it should have given us long ago a true 

 picture of the mental qualities of the builder. This it has failed 

 to do, and as I have shown in another place , the nest in relation 

 to the builder, has been the subject of misinterpretation at 

 more than one point." To the writer referred to, "it is the 

 most palpable example of those reasoning, thinking qualities 

 with which these creatures are unquestionably most highly 

 endowed," and yet we are presently told that " our lack of 

 information relating to the manner in which the nest is made 

 in the majority of species is almost complete." The reader 

 is thus left to wonder how a bird's nest can be the " graphic 

 mirror " of great mental powers, if w^e do not know how it is 

 built. The nest, this writer continues, is primarily a utilitarian 

 structure, and he concludes that it must be a work of great 

 intelligence, because it is so wonderfully adaptive, even though 

 it is generally admitted that " order is heaven's first law," 

 and fitness one of the most striking characteristics of living 

 things, extending even to the parts, properties and behavior of 

 the smallest microscopical cell. To quote further, "A young 

 bird three or four days old is capable of considerable powers 

 of memory and observation, and during the time that elapses 

 in which it is in the nest it has ample opportunity of gaining an 



•« Dixon, Charles: Birds' Nests. London, 1905. 



" See The Home Life of Wild Birds, chap, xi, and The Instinct and Intelligence 

 in Birds. The Popular Science Monthly, vol. Ixxvii, July, 1910. 



