32 BRITISH MAMMALS 



upper jaw are cream-white. On the gray sides there are three or 

 more large spots of whitish colour, which, however, are often 

 broken up by mottlings of a darker tint. There is also a light 

 patch on the back of the head behind the blow-hole, and another 

 near the root of the tail. The back fin is long and pointed, and 

 slopes backwards. In the living animal the black area of the 

 back is really a rich purple, almost iridescent. The skin is of a 

 soft and silky texture, and so thin that it is easily rubbed off. 



This dolphin is an inhabitant of the seas of the North Atlantic 

 and the coast of America and of Europe. About six specimens 

 have been obtained at different times on the west and east coasts 

 of Scotland. One at least was captured on the north coast of 

 Ireland, and the remainder of the examples were obtained on the 

 east coast of England from the Tweed down to the vicinity of 

 the Thames. The white-beaked dolphin is also found in the 

 Baltic Sea. 



Lagenorhynchus acutus. THE WHITE-SIDED DOLPHIN 



This rare form, distributed sparsely about the coasts of the 

 North Atlantic, only seems to have made its appearance in British 

 seas in the vicinity of the Orkney Islands, where it has been 

 obtained three times, including its first description from a stranded 

 skull. It is also stated that it has been met with in the Hebrides. 

 It is perhaps a little smaller in size than the preceding species, 

 and its distribution of colours is pretty much the same, except 

 that the whitish areas on the flanks of the white-beaked dolphin 

 become a continuous white band in Lagenorhynchus acutus, which 

 feature gives it the name of the white-sided dolphin. This white 

 stripe on the flanks extends nearly the whole length of the body, 

 from the flippers to the vicinity of the tail, but away from the 

 middle of the body the white stripe becomes yellowish or even 

 brown. There is sometimes a dark line lying within this long 

 band of darker colour. This dark line starts from the right 

 of the tail and ends on the upper portion of the white patch on 

 the flanks. The mixture of white, yellow, brown, and purple- 

 black gives this dolphin a very handsome appearance. 



