42 INTRODUCTION. 



is doubtless then, to use the words of Scorseby, nc 

 branch of zoology so much involved as that which 

 is entitled Cetology. Some idea of its difficulties 

 may be formed, by considering that although Des- 

 maret, in his Mammalogie (1820-22), enumerated 

 sixty-two species, yet he considered no fewer than 

 twenty-nine of them as doubtful and not estabhshed ; 

 and that Lesson, in 1828, out of eighty -four species 

 which he classified, can vouch for the accuracy and 

 existence of not more than fifty. 



"We have thought it necessary to apprize the stu- 

 dent, in these few words, of the difficulties in which 

 the subject is even now involved, that he may per- 

 ceive it is no easy matter at once to overcome them. 

 From the great rarity of favourable opportunties 

 for examination, we must be cautious even in getting 

 right ; and must hesitate ere we finally reject what 

 has previously been admitted even on insufficient 

 and objectionable grounds. Having said this much, 

 we entirely dismiss this part of the subject. We 

 indulge the hope, that our little Volume may be- 

 come a vade mecum to many a mariner and fisher- 

 man, and that beguiling over it the tedium of a sea 

 voyage, he may thereby be ex;cited to improve some 

 of those opportunities which frequently present 

 themselves to him, though not to us ; and that by 

 making pertinent and judicious observations, he 

 may thus add to the stock of our interesting and 

 important information. 



We now proceed to the comparative anatomy of 

 the Cetacea. 



