36 Bird-Lore to as "a systematic chan<jin<jof environment when conditions are unfavorable to life," a statement assuredly at variance with the bird's desertion of a southern winter home at a season when food is daily increasing for a comparatively barren breeding resort. Again "the effort of the Sparrow to keep warm in winter" is presented as an illustra- tion of one of the primary factors in the struggle for existence, whereas it is believed by many that, given an abundance of proper food, with birds, at least, temper- ature is of comparatively little importance. The definiteness with which the duration of life of various animals is stated is, perhaps, hardly warranted by the known facts; while theories in explanation of the significance of so-called recognition, signaling, warning, alluring, etc., colors are still too numerous to render advisable the treatment here ac- corded them. In this connection we regret to see that Mr. Abbott H. Thayer's very beautiful demonstration ('The Auk,' 1896, p. 125) of the law which underlies protec- tive coloration, a discovery revolutionizing our ideas of what constitutes protective col- oration, is not mentioned. The illustrations are numerous and in- structive, many being reproductions of photo- graphs from nature. We would, however, call the attention of the authors to two or three slips requiring correction: thus the "Arctic Black Duck" figured on page ny with twelve young is evidently one of the Scaups (Aythya), which are not known to lay more than ten eggs; the "Canada Jays" on page 138 are clearly Blue Jays and, un- less we are mistaken, the artist is indebted to Mr. Dugmore's clever photograph of the young of this species, in Scott's 'Bird Stud- ies' (p. 57) ; the intertwined horns on p. 148 are those of deer and not of "elk," as stated, and the male Baltimore Oriole, on p. 267, is shown in the act of nest- building, though, as far as we know, the male has not been observed to assist in constructing the nest. 'Animal Life' is such an admirable piece of work that our desire to aid its authors in eradicating the errors which are bound to creep in a book covering so wide a field, has perhaps led us to appear unduly critical, whereas, in truth, we cannot too highly commend it as an ideal text-book, which, we trust, will speedily replace the antiquated zoologies that have so long blocked the stu- dent's pathway to knowledge. — F. M. C. WHO SAID MICE? (From 'Our Bird Friends') Our Bird Friends; A Book for All Boys and Girls. By Richard Kearton. With 100 original illustrations from pho- tographs by C. Kearton. Cassell & Co. Ltd. London, Paris, New York and Melbourne, 1900. lamo, pp. xvi +215. With the eminently worthy object of stimulating and properly directing chil- dren's inherent interest in birds, Mr. Kear- ton has written a book which seems ad- mirably adapted to accomplish not alone the end in view, but to appeal with equal force to grown folk as well. We have here no rehash of old material or compilation of selected stories for the young, but an original contribution to the literature of ornithology based largely on the author's personal experiences. The book is not local, and while the birds treated are British species, the sub- jective method of presentation renders it almost as attractive to American as to Eng- lish readers. Thus the chapters on ' Nests
