144 The Ottawa Naturalist. [October 



fins, and in some species the hind pair of fins, become enorm- 

 ously developed and project like wide-spread fans from the side 

 of the body. These, no doubt, are effective for protection rather 

 than locomotion. The study of young fishes has, in various 

 ways, an important bearing on the commercial development of 

 the fisheries in rivers, lakes and sea. 



To naturalists, working in the privacy of their homes, 

 the study of young fishes is at once possible and desirable. Few 

 other living objects are more fascinating and beautiful, and the 

 commonest fishes in our waters afford the best material. 



The highest biological results can only be obtained by an 

 exhaustive study of sections under the microscope, and following 

 the lines of Frank Balfour's Elasmobranch papers the St. 

 Andrews biologists have thoroughly studied the minute struc- 

 ture and development of larval fishes, and their popular summary 

 derives additional value from that fact. 



As in all Professor Mcintosh's publications, full justice is 

 done to all that other workers have accomplished. Most of these 

 workers, as Mr. Holt and others, having had the advantage of 

 being trained at St. Andrews in this department of research. 



The literature of the subject is so vast that the book would 

 have been burdened unnecessarily had any attempt been made to 

 include a bibliography. Such a bibliography is, however, acces- 

 sible enough to the specialist, and the synoptical table and 

 practical directions regarding procuring fish eggs for study, added 

 at the end of the volume, are of far more value to the student— B. 



