540 SCIENCE PROGRESS 



good account of parasitic forms in general. It is not intended as a comprehensive 

 treatise, but, rather, is written with the object of systematising the subject, and 

 securing for it a place among the applied biological sciences. 



The introductory chapters afford the student a clear insight into the economic 

 importance of the subject, the nature and effect of parasitism, and the general 

 characteristics and relationships of insects. The prominence given to the mor- 

 phology of the mouth parts — several types being discussed in detail — is much to 

 be commended. The information relative to the noxious forms concerned is given 

 concisely and systematically, and includes much original matter. Certain experi- 

 ments conducted by the author are carefully described, the methods employed 

 demonstrated, and lines of research suggested. Considerable space, in due 

 sequence, is devoted to the Diptera and, as is usual in books of this nature, certain 

 Arachnids, such as ticks and lice, receive attention because of their intimate 

 connection with the spread of disease in man and animals. 



The value of this admirably produced volume is enhanced and its subject- 

 matter rendered more easily assimilable by the numerous and, in general, excellent 

 photographs and line drawings provided. The work calls for little adverse 

 criticism, yet some stricture must be passed upon the treatment accorded to those 

 important insects the Tsetse flies. The information given by no means approaches 

 completeness, and in places is much out of date. Notably is this the case in the 

 systematic portion where the author has followed Griinberg, and entirely ignored 

 the recent and valuable works of Austen and Newstead. Consequently we find 

 but few species mentioned, while the easily distinguished and very important 

 species G. morsitans is not only " said to be almost identical with Glossina longi- 

 palpus " (sic), but is stated to coincide with the latter in its distribution. 



It is to be regretted that these terrible pests have not received the careful con- 

 sideration to which their importance entitles them, and the inadequate treatment 

 of this section of the work tends, unhappily, to mar the general excellence of the 

 whole. 



H. F. C. 



GENERAL 



Reminiscences of Fifty Years' Experience of the Application of Scientific 

 Method to Brewing Practice. By Horace T. Brown, LL.D., F.R.S. 

 [Pp. 82.] (May-June number of the Journal of the Institute of Brewing) 



It is to be hoped that this reprint will be, in some way or other, made available to 

 a wider circle of readers, both scientific and manufacturing, than it is likely to 

 reach in the journal in which it is published. The connection of Pasteur with 

 brewing is already known, at any rate to biologists, although perhaps not so well 

 to manufacturers. The follower of " pure science," on the one hand, and the 

 entirely " practical man " on the other, will both find much food for thought in 

 the pages of this paper. At the present time, too, it is imperative that all con- 

 nected with manufacturing should realise the enormous help that a well-trained 

 scientist, with adequate laboratory accommodation, can be to almost any industrial 

 process. The lack of co-operation between the theoretical and pecuniary side of 

 industry in this country is much to be deplored, and perhaps results, as the author 

 suggests, from the fact that most businesses are in the hands of boards of directors. 

 Such a control means only too often that the directors are not interested in the 

 manufacture as a series of skilled operations, but simply as a somewhat complex 

 machine to produce dividends. Any suggested improvement, therefore, must 

 have to support it a plausible possibility of a fairly quick return on the outlay, or 



