415 



SOME NEW BOOKS. 



Newton's Birds. 



A Dictionary of Birds. By Alfred Newton, assisted by Hans Gadow, with con- 

 tributions from R. Lydekker, C. S. Roy. and R. W. Shufeldt. Part IV., 8vo. 

 London : A. & C. Black. i8g6. Price 7s. 6d. nett. 



Professor Newton's Dictionary of Birds is just completed by the 

 issue of Part IV. now before us. Viewing the book as a whole, one can 

 gather a better idea of its scope, depth, and aims, as well as of its 

 relative value as a work of reference, when contrasted with other 

 ornithological works which have appeared lately. To estimate this 

 book at its true worth is difficult. Its merits, perhaps, were never 

 more justly appreciated than by the reviewer of the first part in the 

 pages of Natural Science, vol. iii., p. 146, who described it as 

 " marking an epoch " in the history of ornithology. None will realise 

 the truth of this better than the serious student of ornithology, who has 

 so many and such humiliating opportunities of sounding the depths of 

 his ignorance. Such will ever feel grateful to the Professor and his 

 colleagues for the vast amount of labour and research which they have 

 expended upon their several contributions. 



The present part contains the Preface and Introduction. This 

 last occupies some 120 pages, wherein is passed in review the whole 

 history of the rise and progress of ornithology from the days of 

 Aristotle onward to the present time. It is really the Encyclopaedia 

 Britannica article recast and brought up-to-date. It should suffice 

 then to say that it preserves all the charm and graceful ease of 

 expression that characterised the original article. 



Perhaps the most interesting of Professor Newton's contributions 

 to this part are those on the Solitaire, Song, and Variation. In the 

 latter the author subscribes to the view that those variations in 

 intensity of colour usually regarded as instances of protective colora- 

 tion — e.g., the pallid colour of desert forms — are really due to climatic 

 influences. The remarkable discontinuous colour-variations which 

 occur amongst certain owls, night-jars, &c., are dealt with under the 

 heading of Dimorphism, or better, as is suggested, Dichromatism. 

 Finally, we are treated to a few brief remarks on abnormal colour- 

 variations, such as Albinism, Melanism, Xanthochroism, and 

 Erythrism ; these are collectively grouped together under the head of 

 Heterochrosis. 



Dr. Gadow's articles maintain their high standard to the end. 

 Indeed in some cases matter will be found which does not find a place 

 in his larger works. In one instance, however, statements are made 

 which certainly may justly demand further qualification. Thus, in 

 describing the skull, certain membrane bones, to wit, the maxilla, 

 pre-maxilla, quadrato-jugal, and jugals are described as modifications 

 of the first visceral arch. This is surely heresy. Accompanying the 

 description is an analytical diagram of the visceral arches, which, if it 



