•90 NOTICES OF BOOKS. 



of Europe alone can it be said that the information is adequate 

 to outline a picture of the life in fresh water. Eecords show 

 conspicuously the uniformity of fresh- water life on the surface 

 of the globe, and many of the forms discussed and figured in 

 the pages of this book are identical with those occurring in 

 Europe, and many more are closely related species. And this 

 uniformity extends beyond the continents of Europe and North 

 America, and is found to extend even to the oceanic islands. 

 As a striking illustration of this geographical uniformity we may 

 mention the researches of the late James Murray, biologist of 

 the Shackleton Expedition, in which he records the occurrence 

 of Rotifera known in Britain in the Antarctic lakes that are 

 frozen solid for many months, and often for several years. The 

 present writer has had a living fresh-water fauna under observa- 

 tion from material obtained from the Green Lake, 16,000 ft., in 

 the Himalayas, in which the organisms were well-known forms 

 of British pond-life. 



The illustrations, which are very numerous, are mostly new, 

 and in many instances specially drawn by the authors for their 

 individual chapters. The authors, one and all, are to be con- 

 gratulated on the production of such a comprehensive work, 

 and the publishers for the presentation of it in such an attractive 

 iorm. 



Aquatic Microscopy for Beginners, or Common Objects from 

 Ponds and Ditches. By Dr. Alfred C. Stokes. 4th edition, 

 revised and enlarged. 5 J in. x 7 J in., ix. + 324 pp., 198 

 figs, in text (New York : John Wiley & Sons, Inc. [London : 

 Chapman & Hall, Ltd.], 1918. 10*. 6c?. net.) 



That the above work has now reached its fourth and enlarged 

 edition is an indication that it has served the useful purpose 

 for which it was intended by the author. In the preparation of 

 this elementary guide to pond-life the needs of the beginner in 

 the use of the microscope have been kept in mind, and little or 

 no use of technical language or strictly scientific description is 

 attempted. For critical work on hydrobiology the larger manuals 

 must be consulted. The introductory chapter (Chapter I) deals 

 with the microscope both simple and compound, the methods of 

 observing and measuring objects, and collecting. The main part 



