THE WHALEBONE WHALES OF THE WESTERN NORTH ATLANTIC. 



119 



The foregoing percentages indicate a remarkable conformity between the 

 American and European specimens in proportions, and such as to be alone almost 

 sufficient to settle once and for all the question of specific identity of this form of 

 whale in the east and west Atlantic. The measurement of the flukes, however, 

 shows a variation of 2 per cent. The importance of this is doubtful, as the measure- 

 ments given by several European observers are not exact. Furthermore, the 

 American measurements were not made by myself in more than two or three in- 

 stances, but by an officer on the whaling steamer, as the flukes were generally cut 

 off before the whales were towed into the station. 



COLOR. 



The descriptions of the color of . physalus given by European authors vary 

 so much among themselves that one might suppose that there was a most extraor- 

 dinary individual variation in this species, as well as a subspeciflc variation. It 

 is true that there is a considerable individual variation in color in all species of 

 whales, and no doubt . physalus exhibits this peculiarity, but the differences 

 which have been cited by authors are largely illusive. The species in question is 

 sometimes said to be black above, at other times gray, or even brown, as shown in 

 the following table : 



BALJSNOPTERA PHYSALUS (L.). EUROPEAN. COLOR. 



It is my opinion that B. physahis is never black when alive. The fact is well 

 known, and is commented upon by some of the authors above cited, that whales 

 rapidly turn dark after death, and that descriptions of the color of stranded speci- 

 mens are, therefore, unreliable. In the Finback whales the epidermis consists of 

 several layers, of which the superficial one is the thickest. When one of these 

 animals is killed and hauled out of the water, the superficial layer at once begins to 

 grow darker, especially if the sun is shining. If a portion of this layer is peeled 

 off, the lighter color of life is found again on the layer below, but in the course of 



