Cetacea. 1531 



A. Having no baleen ; head thickened anteriorly and subtruncate at 

 the apex ; no folds on the under surface of the body — Physeter. 



B. Having baleen ; head attenuated anteriorly ; longitudinal folds on 

 the inferior surface of the thorax — Baleinoptera. 



This last genus was named Baleinoptera by Lacepede, from the 

 character presented by the dorsal fin, and was afterwards denomi- 

 nated Rorqualus by Cuvier. Although this last, derived from the 

 Norwegian, signifying " Whale with folds,"* is without a doubt the 

 most accurate, I believe it to be equitable to retain the first by clearly 

 established right of priority. f 



The external characters of the genus Baleinoptera, to which 

 the animal forming the subject of this notice is referrible, are as 

 follows : — 



Body lengthened, more or less fusiform in shape ; head about as 

 long as the third of the total length of the animal, conical and attenu- 

 ated anteriorly, furnished with short baleen in the upper mandible, 

 and having two blow-holes on the upper surface ; pectoral fins short, 

 and placed at a short distance from the mouth ; dorsal fin small, sub- 

 triangular, placed far backwards and curved towards the tail ; caudal 

 fin bilobed and horizontal ; under-surface of the throat and thorax 

 presenting a series of longitudinal folds, which extend as far as the 

 abdomen. 



The anatomical characters are still too little known to allow of their 

 being used generically or even specifically, but they seem to present 

 very important modifications ; for further details of which I refer the 

 reader to the works of those authors who have written at length on 

 this subject.! 



Several species of the genus Baleinoptera were distinguished and 

 named by some of the older writers ; their descriptions, from their 

 incompleteness, having been insufficient, have induced the greater 

 number of modern naturalists, and amongst these men of the highest 

 scientific authority, to unite them all into one. It must, however, be 

 remarked, that these latter writers have seldom had, during their 

 entire lifetime, the opportunity of seeing more than one of these indi- 

 viduals, whose appearance in our seas is always a rare and acciden- 



* Evidently " Rohr Waale " and not Rorquale, as it has been expressed. 



f It is now ascertained that no Baleinoptera without folds exists in Nature, 

 and that Lacepede and some other compilers were led into error by copying bad 

 figures. 



% See Hunter, Camper, Cuvier, Ravin, Rudolphi, Sandfort, Schlegel, Vrolick, 

 Muller,&c. 



