^"'"igio^"] ^^c^^^ Literature. 225 



from the viewpoints of its enemies, or its prey, as the case may be. (See 

 especially fig. 103 with its explanatory legend.) He also discriminates 

 between the way an animal looks to man and the way it must look to its 

 fellow creatures — i. e., whether the viewpoint is from above or from below, 

 etc., or from the point most vital to the animal. This is perhaps more 

 fully brought out in his recent paper in the 'Popular Science Monthly,' 

 already cited, in which he endeavors to demonstrate that striking and 

 diversified colors tend to concealment, if not at all times, that this is the net 

 result of these supposed conspicuous costumes. The optical hypotheses 

 on which have been based the theories of 'warning-colors,' 'recognition 

 marks,' and mimicry he believes "would never have Uved a day had their 

 originators begun by testing them." His contention is that animals are 

 colored to match their backgrounds. "Scarlet and yellow fruit colors, 

 sky-blue and green leaf colors, on the Macaw, are as absolutely the picture 

 of this bird's background while he is dangerously absorbed in feeding in a 

 tropical fruit tree, as is the little terrestrial mammal's brown the picture 

 of the universal earth-brown on which he lives." Nowhere, however, does 

 the author say that the costumes of animals are for concealment nor does 

 he attempt to show how or why they came to be as they are. It is, how- 

 ever, said (in a footnote to p. 36): "We ourselves attribute all such to 

 natural selection, pure and simple and omnipotent." 



Here and there the explanations and illustrations will doubtless appear 

 to some of Mr. Thayer's readers a little strained and overdone, but they 

 cannot fail to recognize that he has in the main kept well within reasonable 

 bounds, and that he has discovered a key to much that was before con- 

 tradictory and irreconcilable, and that, as a whole, his work is by far the 

 most important contribution yet made to the subject of animal coloration. 

 — J. A. A. 



Howard's 'The British Warblers,' Part IV.' — The good things said of 

 Parts I-III of this excellent w'ork are equally applicable to Part IV, which 

 consists mainly of two monographs, respectively of the Whitethroat and 

 Lesser Whitethroat, the former occupying 23 pages of text and the latter 

 20 pages, each with a colored plate and several photogravures. In addi- 

 tion a colored plate and two pages of texr are devoted, respectively, to the 

 Greenish Willow Warbler and the Siberian Chiff-chaff; there is also an 

 excellent colored plate of eggs, illustrating the eggs of eight species of Brit- 

 ish Warblers, figuring 44 eggs, series of six to eight specimens being given 

 in several instances to show the range of variation. 



I The British Warblers: A History with Problems of their Lives. By H. Eliot 

 Howard, F. Z. S., M. B. O. U. Illustrated by Henrik Gronvold. London: R. H. 

 Porter. 7 Princes Street, Cavendish Square, W. Part 4, December, 1901. Price 

 21 s. net. 



Contents: — Whitethroat, pp. 1-23, 1 colored plate, 4 photogravure plates: Lesser 

 Whitethroat, pp. 1-20, 1 colored plate, 2 photogravure plates; Greenish Willow 

 Warbler, pp. 2, 1 colored plate; Siberian Chiff-chaff, pp. 2, 1 colored plate; Eggs 

 of British Warblers, 1 colored plate; temporary titlepage and contents for Parts 1-4. 



