RORQUALS 159 



species that are really known to exist. But the genus 

 is by no means confined to the northern hemisphere, 

 whence the individuals have been found whose study 

 has allowed of the compilation of the above diagnoses. 

 There are plenty of Bal&noptera in the southern 

 hemisphere, off the coasts of Patagonia, Kerguelen, 

 in the Indian ocean, and elsewhere. These whales 

 have been placed in different species by Gray and 

 others. It may be that such a placing is correct ; 

 and, at any rate, we have before us an instance of 

 a large whale which has an extremely restricted 

 range in the true Greenland whale ; possibly also 

 Rhackianectes is another. But notwithstanding this 

 a priori consideration there seem to be no sub- 

 stantial grounds for retaining such species as B. 

 indie a > B. patachonica, B. schlegelii, etc. As to 

 external characters, the bulk of these extra European 

 Balanoptera are not known, and it is always possible 

 that there may be such characters which would justify 

 their separation specifically. But as to such parts 

 of the skeleton as are known there is no such 

 justification. Sir W. Turner, in his account of the 

 Cetacean remains collected by the Challenger, had 

 no hesitation in referring these bones to some of the 



o 



four known species of Rorquals. Two Pacific whales 

 are known by different names ; and as observation 

 upon some of their characteristics are mentioned 

 by Scammon, some little account will be given here ; 

 but it is probable that B. supkureus is nothing more 

 than B. sibbaldii, while the white band upon the 

 flipper of B. davidsoni seems to show its identity 

 with B. rostrata. 



