WHALEBONE WHALES. 19 



larger dimensions, and is believed to have a few more vertebrae in the back- 

 bone. 



Rudoiphi's Fin- The next species in point of size is Rudoiphi's fin-whale (B. 



Whale. borealis), which attains a length of from 40 to 45, or occasionally as 

 much as 52 feet. In colour it is bluish-black above, with oblong white spots, 

 while the under-parts are more or less white ; the under-surface of the flukes, as 

 w^ell as both sides of the flippers are, however, coloured like the back. The 

 back-fin is smaller, and placed further back than in the lesser finner : while the 



THE LESSER FIN-WHALE (A nat. 



flippers are very small, equalling only one-fourteenth of the total length. There 

 .are thirteen pairs of ribs ; and the whalebone is black. 



This species is much rarer than the other rorquals, and does not appear to have 

 been recorded from the Pacific. It ranges as far south as Biarritz, and migrates 

 northward in summer as far as the North Cape ; and either this or a closely-allied 

 species occurs in the seas around Java. Of specimens recorded from the British 

 Islands, the first was stranded on the shores of the Firth of Forth in 1872 ; the 

 second was caught in the river Crouch, in Essex, in 1883, a third in 1884 in the 

 Humber, a fourth in the Thames at Tilbury in 1887, and a fifth in the Medway in 

 1888. On the coasts of Finrnark the numbers of this whale are very variable, and 

 while it is a constant summer visitor on the Western seas, it only occasionally 



