REVIEWS 499 



haunted the neighbourhood of the islands from July till October 1920, as 

 recorded in The Scottish Naturalist (Nos. 107-108, 1920)." He adds that this 

 keeper claims two previous occurrences of this mammal off the islands during 

 the last forty years. 



The work concludes with brief notes on " Mammals extinct in the British 

 Islands within Historic Times." The five following species are enumerated : 

 Wolf, Brown Bear, Beaver, Reindeer, and Wild Boar. The Elk certainly, 

 and the Lynx probably, should have been included. 



Each volume is provided with a table of contents, but these, as also 

 the preface, are printed on un-numbered pages. A useful index is provided. 

 For some reason the pagination of the two volumes is discontinuous, but 

 the plates are consecutively numbered from one to fifty, there being twenty- 

 five in each part. The classification followed is that adopted by Mr. Millais 

 in his A History of British Mammals. 



As the author points out in the preface, the fact that British mammals 

 are comparatively few (seventy species) has enabled him to be considerably 

 freer with the allocation of space on the plates than was the case with his 

 birds. This has made it possible to devote a single plate, and in some cases 

 even two, to one species. Thus it is that the Mountain Hare and the Stoat 

 are illustrated both in their winter and summer pelages on separate sheets. 

 While these pictures possibly make us wish that Mr. Thorburn could have 

 treated all his beasts in similar fashion, his grouping of several forms on a 

 single plate is often so charmingly done that we admire these almost as much. 

 Plates 9 (Shrews) and 26 (Harvest and Wood Mice) are good examples. 



If there is any criticism to be made of the artist's beautiful work it is 

 that some of his mammals lack character. The Wild Cat (Plate 10), though 

 snarling and evidently disgruntled, is by no means a convincing cat. It 

 lacks character. It is not really "catty." Nor is the Fox (Plate 11), in 

 spite of his flamboyant brush, characteristically " foxy." The same sort 

 of remark would be applicable to several others. 



The majority, however, represent Mr. Thorburn at his best. It is difficult 

 to conceive of anything more delightful than the Doormouse (Frontispiece, 

 Vol. II) or the Stoat in winter pelage (Plate 22) or the Common Rabbit 

 (Plate 36) . Others that are particularly striking and pleasing are the Chartley 

 and Chillingham Bull's-heads (Plate 41), the Stoat in summer pelage (Plate 

 21), and the Mountain Hares (Plates 34 and 35). 



The pen-and-ink sketches, as previously remarked, do not compare with 

 Mr. Thorburn's incomparable brush work. Very few, incidentally, are 

 included in the second volume. 



The publishers as well as the author deserve congratulation for successfully 

 completing this beautiful work, which will be much valued by mammal 

 students and lovers of art. 



W. R. 



The Mechanism of Life in Relation to Modern Physical Theory. By James 

 Johnstone, D.Sc, Professor of Oceanography in the University of 

 Liverpool. [Pp. xii + 248.] (London : Edward Arnold & Co., 1921. 

 Price 15s. net.) 



If this book were expurgated and thereby reduced to about half its present 

 size, it might form a useful introduction for those who, without being experts, 

 are interested in the study of biological energetics from the standpoint of 

 modern science. The physiological diagrams are nicely drawn, and there 

 are many instructive illustrations of energy transformations in physics and 

 chemistry. 



As it stands, however, the work is a hodge-podge of a variety of undigested 

 generalisations on Physical Science, Psychology, Philosophy, Relativity, 



