STRANDED ON THE BRITISH COASTS. 151 



feet long when adult, and its baleen is usually black in colour, 

 though spnie of the blades are pai'tly white, with white hairy 

 fringes of the fine, silky texture and curly character noted aloove. 

 An elaborate account of this species has I'ecently been given by 

 Andrews (1916); while the memoir of Allen (1916, p. 234) may 

 also be consulted for its coloiation and other charactei's. The 

 maximum length of B. borexdis is said to be about 53 ft. 



(3) Common Rorqual {Balcenoptera physcdus L.). 



Including three of the individuals which weie originally 

 referred to B. horealis, as above explained, this species is 

 represented by eight records : namely, North Devon (Feb., 1913), 

 Kerry (Feb., 1914), Northumberland (May, 1915), Caithness 

 (July, 1913), Donegal (Aug., 1913), North Kent (Oct., 1914), 

 Scilly Islands (Oct., 1917), and Caithness (Nov., 1914). 



The Common Rorqual usually reaches a length of 65 to 70 feet 

 in Northern waters. Its baleen-blades are for the most part 

 slate-coloured, with darker and lighter longitudinal streaks; but, 

 as pointed out in the account of the preceding species, a number 

 of them at the anterior end of the right series are white. Their 

 hairy fringes are yellowish in colour. The food consists partly of 

 fish and partly of pelagic Crustacea, the species showing a , 

 preference for the latter form of diet (Collett, 1912, pp. 581, 582). 

 Like the Lesser Rorqual, it occurs of!" the Norwegian coast at all 

 times in the year. 



B. physcdus is known to be very variable in colour; and to such 

 an extent that various forms of the species have been distinguished 

 by the Norwegian whalers. For information on this subject see 

 Cocks (1884, p. 458 ; 1887, p. 2L5), True (1904, p. 119), and Allen 

 (1916, p. 181). The specimen here recorded from the Scilly 

 Islands appeared to have a good deal of white on the dorsal 

 surface, a type of coloration which is unusual for this species. 

 But I have recently been informed by Mr. King, who took the 

 photographs published on p. 13 of my Report for 1917, that in 

 his opinion much of the white colour observable was due to the 

 loss of the skin in patches and the consequent exposure of the 

 underlying blubber. 



ODONTOCETI or TOOTHED WHALES. 



Fam. Physeterid^. 



Subfam. PHYSETERINiE. 



(4) Sperm Whale {Physeter catodon L.). 



Three records, from E. Caithness (May, 1917), Gaiway (Sept., 

 1916), and Inverness (Dec, 1913). 



The Sperm Whale, which occurs principally in the warmer 

 seas, is remarkable for the striking ditfeience in size between the 



