262 'THE WHALEBONE WHALES OF THE WESTERN NORTH ATLANTIC. 



the other hand, the measurements of the various skulls show considerable dis- 

 crepancies. These do not, however, tend to divide the skulls into two groups, 

 according to locality. In this connection it is necessary to hold in mind that the 

 majority of the skulls are those of young individuals. 



8. The length of the first rib is the same in European and American skele- 

 tons of equal size. The breadth of the first rib at the distal end is variable in 

 both series of specimens, and often differs much on the two sides of the body in 

 the same specimen. 



9. The sternum is variable in shape, with no constant difference between 

 European and American specimens. 



10. The scapula has the same characteristic form in both European and 

 American specimens. 



While there are many points regarding the Nordcaper that need to be further 

 investigated, there is at present, so far as can be ascertained from the material 

 available, no valid reason for separating the American from the European specimens 

 as distinct species. 



OPINIONS REGARDING THE IDENTITY OF THE RIGHT WHALES OF THE EASTERN AND 

 WESTERN ATLANTIC (INCLUDING WITH THE LATTER COPE's B. CISARCTIGA.^ 



It has seemed to me desirable to sum up again, as did Holder in 1893, 

 the opinions of cetologists regarding the relationship of " B. biscayensis " to 

 B. cisarctica. 



It is well known that several systematic writers of the eighteenth century, fol- 

 lowing for the most part the more or less indefinite statements of Zorgdrager and 

 Martens, distinguished two species of northern Right whales, the Greenland or 

 Spitzbergen whale and the Nordcaper. The story of the union of these species 

 by Cuvier and their subsequent separation by Eschricht is familiar to every cetolo- 

 gist. Cuvier was, of course, acquainted with the fact that the Basques pursued 

 Right whales on both sides of the North Atlantic, 1 but as he regarded all whales 

 of the genus Balcena in these waters as forming one species, any critical considera- 

 tion on his part of differences between those of the western and those of the east- 

 tern Atlantic was precluded. 



A principal object of the researches of Eschricht upon the northern Right whales 

 was the demonstration of the correctness of the suspicions which he entertained as 

 early as 1840 that the Nordcaper was specifically distinct from the Greenland Right 

 whale, 2 but he did not have under special consideration at any time the question of 

 the identity of American specimens of the former species with those from the Euro- 

 pean coasts. Indeed, so far as I am aware, there were no American specimens of 

 B. biscayensis in European museums in his day. 3 Nevertheless, in the work Om 



'See ESCHRICHT and REINHARDT, " Om Nordhvalen," Videns. Selsk. Skr.,5 Rakke, naiurvidens. 

 og math. Afd., 5 Bd., 1861, p. 479, foot-note 5. " See Comptes Rendus, 1860. Separate, p. 2. 



"See GASCO, " Intorno alia Balena presa in Taranto, Atti R. Ac ad. Napoli, 1877, p. 

 Separate, 1878, pp. 12-13. 



