382 SQUAMD.E. 



Shark is migratory, and I have never known it arrive on the 

 coast of Cornwall before the middle of June ; but afterwards 

 it becomes abundant, so that I have known eleven taken in 

 one boat, and nine in another, in one day. The injury they 

 inflict on the fishermen is great, as they hover about the 

 boats, watch the lines, (which they sometimes cut asunder 

 without any obvious motive,) and pursue the fish that are 

 drawn up. This, indeed, often leads to their own destruc- 

 tion : but when their teeth do not deliver them from their 

 diflticulty, they have a singular method of proceeding, which 

 is by rolling the body round so as to twine the line about 

 them throughout its whole length ; and sometimes this is done 

 in such a complicated manner, that I have known a fisherman 

 give up any attempt to unroll it as a hopeless task. To the 

 Pilchard drift-net this Shark is a still more dangerous enemy, 

 and it is common for it to pass in succession along the whole 

 length of the net, cutting out, as with shears, the fish and the 

 net that holds them, and swallowing both together." 



The specimen described measured fourteen inches ; the 

 head depressed, broadest between the eyes, which are lateral ; 

 half-way between the eyes and the point of the nose are the nos- 

 trils, linear, directed obliquely downwards and backwards, the 

 most inferior portion covered with a valvular fold of skin ; the 

 eyes round and rather large ; the mouth forming half a circle, 

 the teeth in this specimen very minute, — the cutting teeth on 

 the left hand in the representation at page S70 belong to 

 this species, and were from a specimen about six feet in 

 length, in each jaw of which there are three rows, those im- 

 mediately in the centre, to the number of four, being calcu- 

 lated more for holding than cutting ; the number of rows of 

 teeth in the Sharks are said, and I believe con'ectly, to in- 

 crease with age, and vary in this species from one to six. 

 The branchial apertures are five, the fourth placed over the 



