266 MAMMALS AND BIRDS OF THE NORTH PACIFIC 



Up to 1883 two skeletons, one in the Imperial Museum in St. Petersburg and 

 the other in the collection of the Imperial Academy at Helsingfors, and two ribs 

 preserved in the British Museum, were all the remains of the northern sea-cow 

 known to science. In that year, however, Dr. Stejneger was sent to Bering Island 

 by the United States National Museum in search of skeletons, and within two years 

 he succeeded in procuring a number of more or less incomplete skulls, together with 

 vertebrae and other bones from the sand of the island. Many of these were found 

 so far from the shore that it was suggested that the island must have been elevated 

 since Bering's time, a supposition confirmed by the discovery of a skeleton near its 

 centre. 



Dolphins and Although the cetaceans of the North Pacific are very similar to 



Killers. those of the North Atlantic, there are some peculiar types. Among 

 the forms common to both oceans, the bottle-nosed dolphin is apparently indigenous 

 to all the warmer seas, as are also the common dolphin and Risso's dolphin. The 

 blackfish is likewise widely distributed, although the North Pacific form is distinct 

 enough to be ranked as a separate race, while by some it is regarded as a species 

 under the name of Globioceplialus scammoni. The killer of the Pacific has likewise 

 been distinguished from the one inhabiting the Atlantic, although there is apparently 

 but one widely spread species. Allied to the true killer is the lesser killer 

 (Pseudorca crassidens), which is as cosmopolitan, although apparently more common 

 in the Pacific than elsewhere. It is uniform black, with a total length of about 

 14 feet, and has generally eight teeth on each side of the upper jaw and ten on each 

 side of the lower jaw. The porpoise inhabits the Pacific as far north as Alaska. 



Lesser Sperm- The sperm-whale is likewise an inhabitant of the North Pacific, 



wnaie. as i s a i so Cuvier's beaked whale, referred to in the chapter on .North 



Atlantic mammals. More noteworthy is the lesser sperm-whale (Cogia breviceps), 



which does not exceed 10 or 12 feet in length, and is the sole representative of its 



genus. Widely distributed, this species is black above and paler below, with a large 



back-fin and short, sickle-shaped flippers. The muzzle is short, and the blow-hole 



crescentic in shape, and placed on the top of the head in front of the eye, somewhat 



to the left of the middle line. 



The largest North Pacific representative of the whalebone-whales 

 Grey Whale 



is Sibbald's fin-whale, which occurs at all seasons off the Californian 



coast. The common rorqual is represented in the North Pacific by a variety, as 

 is also the hump-backed whale. An exclusively Pacific type is the grey whale 

 (Rhachianectes glaucus), which represents a genus by itself. This remarkable whale, 

 which is peculiarly a coast species, and frequently runs aground in the surf where 

 it remains till floated by the next tide, attains a length of 40 or 50 feet, and 

 has flippers 6 feet long, but no back-fin. In colour it is bluish grey with pale 

 mottlings, becoming paler below, though occasionally black all over. The yellow 

 whalebone is short and the oil poor both in quality and quantity ; nevertheless, the 

 ease with which it is caught has led to this whale being well-nigh exterminated. 

 The skeleton presents several curious peculiarities. 



Black The right -whales form a small group characterised by the 



Right-Whale, absence of a back-fin, the relatively large size of the head, the arch- 

 like curvature of the edges of the lower lips, the shortness of the five-toed flippers, 



