28 



SCIENCE 



[N. S. Vol. XXX. No. 757 



In the elaborate and excellent American 

 Nature Series, now in course of publication, 

 Knowlton's " Birds of the World " forms the 

 third issue under the head of " Natural His- 

 tory," having been preceded by Jordan's 

 " Fishes " and Kellogg's " American Insects." 



Writers of bird-books sometimes hear the 

 remark in tones of disparagement : " But you 

 describe so few birds! The robin and the 

 chipping sparrow are very well in their way, 

 but we should like to read about the bird-of- 

 paradise, and the toucan as well." Such 

 critics will have no case when they handle 

 Mr. Knowlton's weighty volume, for in this 

 treatise he reviews the entire class; there are 

 over eight hundred large pages, and these are 

 embellished with nearly two hundred and fifty 

 illustrations. 



When we reflect that the birds of the world 

 comprise upwards of twelve thousand species, 

 and that the major and minor celebrities form 

 a great company, with an already vast and 

 ever-growing literature, the labor and diiEculty 

 of preparing a well-balanced hand-book for 

 the entire field, which shall be both useful 

 and interesting, is a task of no holiday order. 

 In our opinion the author has succeeded ad- 

 mirably in nearly every respect. His work, 

 from necessity a compilation, is certain to 

 prove very useful; it is published in attractive 

 form, and possesses a large fund of interest- 

 ing facts concerning the structure, classifica- 

 tion and general habits of the better known 

 and more important members of the entire 

 avian group. 



The body of the work is preceded by several 

 sections of an introductory nature, dealing 

 with the general characteristics of birds, with 

 their distribution, migration and zoological 

 relations. This part further includes a very 

 compact and valuable chapter on the Anatomy 

 of Birds by Mr. Frederic A. Lucas. The fact 

 that the entire work has passed under the 

 " editorial censorship " of Mr. Eobert Ridgway 

 should tend to discourage those critics whose 

 appetite is whetted by their ability to find 

 mistakes. Twenty-one chapters follow on the 

 "orders" in the classification adopted by the 

 author, beginning with the sole occupant of a 



subclass, the famous Archwopteryx, which has 

 been pronounced three fourths " bird " and 

 one fourth " reptile," and ending with the 

 great order of Passeriformes, said to embrace 

 over seven thousand species, or more than one 

 half of all known birds. This is followed by 

 a full, and therefore useful index. 



Dr. Knowlton's book is presumably not one 

 of the kind intended to be read from cover to 

 cover, but like Newton's " Dictionary of 

 Birds " and other extended treatises, is to be 

 used as a compendium for reference. The 

 author has surveyed the most pertinent litera- 

 ture so well, and has preserved so sane a 

 judgment in dealing with it, that he is a guide 

 to be trusted on all matters of which he treats. 

 His errors will be found to be chiefly those of 

 omission. 



Some criticism could be made of the au- 

 thor's style, but this is certainly even and 

 clear, and probably well adapted for a refer- 

 ence-work of this kind. The reviewer has 

 found no errors of consequence, those noted 

 being of a rather trivial order, as when in 

 speaking of the night-hawk, Mr. Knowlton 

 says (p. 43) : " Some individuals " spend " the 

 summer in Alaska and the winter in Pata- 

 gonia," which may be true, but is an assump- 

 tion, to be tested only by the marking of indi- 

 vidual birds. The " banding " or " ringing " 

 of individuals to obtain exact data on migra- 

 tion, first tried with a measure of success on 

 the Phoebe by Audubon, has been taken up 

 rather recently, and with the promise of yield- 

 ing very valuable results. 



We miss from the introductory matter any 

 summary of the modern work on the instincts, 

 intelligence or general behavior of birds, a 

 subject no longer of interest to psychologists 

 only. In speaking of the absence of " hook- 

 like processes of the ribs" in Archwopteryx 

 as a " decidedly reptilian character " it should 

 perhaps be noted that the New Zealand lizard- 

 like Hatteria possesses them, as well as the 

 crocodile and alligator, and the latter, more- 

 over, builds a nest which is guarded by the 

 male. 



We can not subscribe to the view that " we 

 are without an adequate theory of birds' 



