point and is, alas, one that is commonly neglected. His advocacy 

 of a green safelight is another good point which should be adopted 

 when possible. Only those who spend long hours in a dark-room 

 illuminated in this manner know the incalculable relief afforded 

 by this simple means. 



We cannot agree with Mr. Barnard, however, in his advocacy 

 of home-made light filters. This is work demanding the utmost 

 scientific accuracy, as a rule far beyond the powers of the amateur, 

 however willing. It is at the best a messy task, and generally 

 costs more in the end than a filter prepared under scientific 

 conditions. 



In a later chapter the author deals with photographic processes. 

 This is quite encyclopaedic in character ; and bearing in mind the 

 critical necessities of the work, we regret to find no mention of 

 paraphenyelene diamine among the developers. In spite of the 

 difficulties attending its use, there is a decided gain in resolution 

 of fine detail which more than compensates for its disadvantages. 

 We are bound to disagree with Mr. Barnard on the subject of 

 contact printing with regard to lantern slides. We are most 

 emphatically of opinion where absolute sharpness is necessary (as 

 in a microscopical subject) that it is by far the better plan to 

 make them through the camera. 



The book is written throughout in the clearest and most attrac- 

 tive style. It reflects the greatest credit on Mr. Barnard, and 

 should prove a useful aid to the photomicrographer for a very 

 long time to come. Our greatest regret is that at the end of the 

 book the publishers have seen fit to reproduce Mr. Barnard's fine 

 examples by the collotype process. In a work published at this 

 price we think that these should have taken the form of actual 

 photographic prints from the original negatives ; as it is, we cannot 

 consider the results as published do the author's photographs 



justice. 



A. C. B. 



The Life of Crustacea. By W. T. Caiman, D.Sc. 7f x 5 in., 

 xvi -f 289 pages, 32 plates, and 85 figures in the text. 

 London, 1911. Methuen & Co. Price 6s. 



In this new work on the Crustacea Dr. Caiman has given a 

 most attractive account of this very important group of animals 

 mainly from the point of view of their habits and adaptations to 



