REVIEWS 323 



in our knowledge are to be filled, more attention should be drawn to them, 

 and the industrial applications should be kept more clearly in the sight of 

 the reader, as a powerful stimulus in bringing this about. Work which 

 should be done is left, not because it is too difficult, but because no one 

 thinks of doing it. The enthusiasm with which a new subject is begun 

 may easily be wasted unless the student feels there is something for him 

 to do — and the writer of a textbook has a responsibility in directing thought 

 into fields which will bear fruit in due season. Though we admire the many 

 good qualities of the book, we think that, in this respect, it has fallen short 

 of the ideal. 



G. S. Adair. 



What Bird is That ? By Frank M. Chapman, Curator of Birds in the American 

 Museum of Natural History. [Pp. xxvi+ 144, with 8 coloured plates 

 and 9 text illustrations.] (New York : D. Appleton & Co. Price 

 $1.25 net.) 



This book is written for beginners in the study of United States birds. It is 

 produced on new lines and is, as far as it goes, extremely useful. The chief 

 feature of the publication lies in the coloured plates, eight in all. Each 

 plate represents a case of museum specimens, each case including all the birds 

 that occur together at certain times of the year. Thus one case shows per- 

 manent residents, another winter visitants, and others late and early spring 

 migrants. The student can thus see at a glance all the birds that should be 

 present during any given month by turning up the appropriate cases. As all 

 the birds are drawn to the same scale, the comparative size of a bird as ob- 

 served by the student can be made accurate use of — a very valuable feature. 

 Unfortunately the book is restricted to land birds found east of the Rockies, 

 and so deals with only a part of the American Avifauna. 



The coloured plates are well reproduced from excellent originals. It is 

 a pity, perhaps, that they are so extremely small, but as the author claims, 

 owing to the care in production, no essential details have been lost thereby. 

 The pictures differ from most bird illustrations in the extraordinarily good 

 and characteristic poses given to each species. If the paintings are indeed 

 copies of " stuffed " birds, the originals must be veritable gems of the art 

 of taxidermy. Indeed, considering the restricted scope of the volume, 

 this appears to me to be its most valuable feature, for it converts it from a 

 beginner's book to one that should be in the hands of all bird artists and taxi- 

 dermists. 



The letterpress consists of " labels " for all the birds depicted. Each label 

 gives brief details of colour, distribution, migratory dates, etc. The last- 

 named is a particularly useful feature, as it enables the student to put exact 

 dates to the cases to suit his particular locality, accurate migratory dates 

 being given for at least five divergent centres with each " label." 



The few text figures are so poorly printed that they might well have been 

 omitted. The " map " of a bird, giving the correct descriptive terms to 

 the various components of its surface anatomy, should be of value. There 

 is also a good index. 



Wm. Rowan. 



Action de la Chaleur et du Froid sur I'Activite des etres Vivants. Par 



Georges IMatisse. [Pp. ii-l-556.] (Paris: Emile Larose, 1919.) 



This is a comprehensive discussion of the effect of different temperatures 

 on living organisms. From the crude test of the extremes of temperatures 

 which may be survived, the author passes on to consider the effect of variation 

 in temperature at moderate temperatures. 



There is a marked difference between warm- and cold-blooded animals 



