Editorial 81 



The work has been under way for many years and it seemed 

 to some of us as though it never would make its appearance, but 

 the long awaited results are not in the least disappointing. To be 

 sure, one may pick flaws here and there, but where lives the 

 scientist who was ever quite satisfied with another's work? 



Following the introduction by Ward, are excellent chapters 

 dealing with the conditions of existence in fresh water, by V. E. 

 Shelford, and methods of collecting and photographing, by Jacob 

 Reighard. The Bacteria are treated by E. O. Jordan, the Algas 

 by E. W. Olive and Julia W. Snow, and the larger aquatic plants 

 by Raymond H. Pond. The treatment of the various zoological 

 groups from the Protozoa to the aquatic vertebrates — the work 

 of numerous specialists — occupies more than three-fourths of the 

 book. A chapter on sanitary and technical problems, by Whipple, 

 closes the volume. 



From the standpoint of one interested in fish culture it seems 

 regretable that a key to the commoner forms of the higher plants 

 that are fully aquatic, such for instance as the pond weeds, was 

 not included, but there are numerous good works on systematic 

 botany which may readily be obtained. One misses also any 

 reference to the Sporozoa, the Protozoan forms so commonly 

 parasitic on fishes, but this was probably conditioned by the 

 inability to find any specialist to undertake this little-known 

 group. No synoptic treatment of the fresh-water vertebrates is 

 attempted, owing to limitations of space; but systematic works 

 on the fishes, amphibia and reptiles are easily available in other 

 literature, and Prof. Eigenmann's general discussion is interesting 

 and valuable. 



The chapters dealing with the animal groups most closely 

 related to the economy of fishes, either as parasites, or as food, 

 are all well done. For the first time in the history of American 

 zoology do we find a comprehensive discussion of the parasitic 

 flat worms and round worms. The biological interest in these 

 groups is necessarily very great and their economic importance 

 can scarcely be overestimated; but, owing to the scattered 

 nature of the literature, it has been exceedingly difficult to do 

 satisfactory work on them. Professor Ward's complete and 

 authoritative treatment of these groups is therefore of special 



