THE SPINOUS SHARK. 



213 



The color of the Picked Dog-fish is slaty gray above, diversified, when young, with 

 a few white spots, and the under parts are yellowish white. The skin is rough if 

 stroked from the tail to the head, and smooth when rubbed in the reverse direction. 

 The average length of this species is about eighteen inches. 



The GREENLAND or NORTHERN SHARK (Daldtias boredlis) must receive a brief notice, 

 as it is frequently mentioned in accounts of whaling voyages. 



This species is remarkable for the very small proportionate size of the fins, and for 

 the manner in which the points of the teeth diverge from the centre of the jaw. It is 

 a great foe to the whale and whalers, and is so heedless of danger when intent on 

 satisfying its hunger, that it will follow a dead whale to the ship, mix boldly with the 

 men who are engaged in cutting the blubber, thrust its head boldly among them, and 

 at every bite scoop out lumps as large as a man's head. 



So deeply engaged is the creature in this interesting occupation, that even if a 

 man should slip into the water from the smooth oily skin of the whale, the Greenland 

 Sharks take no notice of him, but continue their depredations on the whale. Even 



PICKED DOG-FISH. -/4caflA/as vulgarls. 



after the long whaling knife has been thrust through its body, it will dart off for the 

 moment on feeling the wound, but will soon return to the same spot and continue its 

 banquet. It also feeds on crustaceans and small fishes. Many specimens are nearly 

 if not wholly blinded by a parasitic animal technically called Lerncea elongata, some 

 three inches in length, which fastens upon the corner of the eye and lives upon its 

 fluids. 



The color of this species is brown with a shade of deep blue. Its length, when full 

 grown, is about fourteen feet. 



ANOTHER curious species of Shark, called appropriately the SPINOUS SHARK (Echi- 

 norhinus spinosus), is notable for the spine-topped bony tubercles which are scattered 

 over the surface of the body. The greater number of these spinous projections are 

 boldly hooked, in a manner not unlike the thorns of the common bramble, and the 

 points are directed backwards ; others, however, are quite straight and stand upright. 

 The object of these curious spines is not clearly known. They are very small in 

 proportion to the size of the fish, and it is said that the males are more thickly studded 

 with them than the females. 



