422 



should be extremely useful to all those taking an intelligent 

 interest in the study of fresh-water organisms and who would 

 like, without going to the expense of buying the monographs on 

 all the different groups, to be able to name the various forms they 

 meet with, or at least to place them approximately in their 

 respective genera. To the specialist, of course, the book, in its 

 present form, will hardly appeal, so far as his own department is 

 concerned. 



Two suggestions may perhaps be permitted. In the first place 

 it seems to us that in a work resting its claim to recognition 

 almost entirely upon its usefulness in helping the student to name 

 his specimens, a very determined effort should be made to include 

 every known species, not necessarily of the world, but at least of 

 some such area as Europe, for instance. This is, no doubt, for 

 many reasons, an almost impossible ideal, and it is not surprising 

 that the editors of the •" Einfachste Lebensformen " should have 

 decided not to strain after it. But it must be admitted that the 

 value of a work of this sort would increase not merely in 

 arithmetical, but in geometrical progression the nearer complete- 

 ness could be approached. Should a further edition be called for, 

 it is to be hoped, therefore, that efforts will be made to include 

 all the known European forms. 



The second point is that the addition of a few of the synonyms 

 under which the different species are to be found in one or two of 

 the best-known monographs, would be an extremely useful 

 feature. It would certainly increase the value of the book for 

 English workers with the microscope. D. J. S. 



The Microtomist's Yade-Mecum: A Handbook of the 

 Methods of Microscopic Anatomy. By Arthur Bolles 

 Lee. Eifth Edition : xiv + 532 pages, 3 figures in the 

 text. London, 1900 : J. & A. Churchill. Price 15s. 



This w-ork is so well known to microscopists, and so much 

 valued by them, that it is hardly necessary to refer to it here in 

 detail. It may be pointed out, nevertheless, that the author, in 

 issuing this fifth edition, has taken full advantage of the oppor- 

 tunity to very thoroughly revise the text throughout, and to 

 include references to all the really useful methods that have been 



