2 66 Dzcellers of the Sea and Shore 



to throw themselves ashore in their efforts to escape 

 these marauding hands. 



To the dolphins, also, belongs that odd creature the 

 sea unicorn, or narwhal {Monodon monoceros) . In 

 this whale the teeth are undeveloped, save in the male 

 who has one long twisted tusk that projects straight 

 out in front fully one half the length of the body. As 

 the narwhal is twelve feet long from snout to tail, it 

 will be seen that this tusk, notwithstanding that it has 

 a narrow central cavity, constitutes a considerable piece 

 of ivory. It is, in truth, hunted only for this tusk, the 

 whalers seeming to attach little value to the carcass. 

 Despite the formidable aspect of the tusk, its use to the 

 animal is very obscure. Certainly the narwhal does not 

 — as does the swordfish — charge boats and pierce them 

 with its weapon. Nor has it been observed ever to use 

 it in any other manner, offensive or defensive. It is a 

 peaceable and even a playful creature; and this, to- 

 gether with the fact that it swims in small herds in the 

 icy waters of the North, where it feeds on small fishes, 

 crustaceans, and cuttlefishes, is about all that is known 

 with certainty regarding its habits. 



Closely akin to the dolphins are the porpoises. The 

 fact is, between the two the fundamental difference 

 seems slight, and what does exist is to be found chiefly 

 in the dentition of these animals. The teeth of the 

 typical dolphin are conical and pointed, and in numer- 

 ous ways they strikingly resemble those of reptiles; 

 whereas in the porpoise the teeth are grooved and flat- 

 tened, or shovel-shaped, at the crowns. Porpoises are 

 without doubt the commonest of all the cetaceans. But 

 the majority of species frequent the coasts, bays, and 



