Introduction 



WITH THE PUBLICATION of the second part of Fishes of the Western 

 North Atlantic it seems desirable to restate briefly the purposes and aims of 

 this series, particularly for those who may not be familiar with Part One. In ich- 

 thyology, as in other sciences, much of the early work was devoted to purely de- 

 scriptive accounts which appeared in numerous publications here and abroad, and 

 although new species are still described occasionally, a stage of relative stability has 

 been achieved in our knowledge of the species which occur in the western North 

 Atlantic. At this time, therefore, it seems particularly important to bring together 

 and synthesize the vast amount of information which has been amassed in the past 

 and thus make it available to both public and marine biologists. It is intended that 

 each article in this series shall be a critical review and revision rather than a mere 

 compilation of previously published works, and, as pointed out in the Preface to 

 Part One, that it be "written on the premise that it should be useful to those 

 in many walks of life — to those casually or vitally interested in the general phe- 

 nomena of life in our waters, to the sportsman whose interests are closely associated 

 with pleasure and relaxation, to the fisherman whose livelihood depends upon know- 

 ledge of where fishes are gathered together, as well as to the amateur ichthyologist 

 and the professional scientist." 



Part One, published in 1948, dealt with the Lancelets, Cyclostomes and Sharks 

 of the western North Atlantic. The present publication, treating of Sawfishes, Gui- 

 tarfishes. Skates, Rays and Chimaeroids, brings to completion a further effort in the 

 over-all purpose of this series. In general the format and treatment of these groups 

 are the same as in Part One. In conformance with general policy, these studies also 

 are written for the layman as well as the specialist and are critical reviews rather 

 than perfunctory compilations. The text, together with meticulously accurate illustra- 

 tions, should leave no place for confusion in the reader's mind. As in Part One, 

 under each species will be found not only a detailed description and the distinctive 

 characters which set it apart from its nearest relatives, but notations on color, size, 

 general habits, abundance, range, relation to man, and occurrence. The geographical 

 range of the fishes described remains essentially the same — the western half of 

 the North Atlantic, including the adjoining gulfs and seas, from Hudson Bay south- 

 ward to the Amazon River. Numerous species found in other parts of the globe are 

 often referred to, and occasional species from adjoining seas are described. 



