THE SHARKS AND RAYS. 421 



When hooked, this shark not infrequently comes to the 

 surface to shake out the hook, failing which, it revolves in 

 the wat^r with great rapidity, the line scoring into the 

 roughly granulated skin and tying the fish in a knot. 

 This shark is deep blue above, lighter on the pointed 



snout, white beneath. The upper lobe of the tail is 

 notched ; the eye has the usual nictitant membrane ; but 

 the spiracle, so characteristic of many members of the 

 family, is absent. It feeds on mackerel, pilchards, and 

 ground -fish. This shark is supposed to deposit its egg- 

 cases in winter when absent from our shores. 



The Tope, more familiar on our coasts, and known 

 locally as the " Silver Dog " or " Rig "—the " School " 

 Shark of Australian seas — occurs along the 

 south and east coasts. I have caught them 

 at Bournemouth over 4 feet in length, as they feed at mid- 

 water, and are fond of following up the hook and seizing 

 a whiting already hooked. This shark, which is grey 

 above and white beneath, grows to a length of over 6 

 feet, and is slender in form. The eye has a nictitating 

 membrane, and a small spiracle is present. The teeth, 

 in three rows, are triangular and serrated. When fresh 

 caught, this shark has, like the porbeagle, a rank smell. 

 It is viviparous, extruding one or two score of young 

 at midsummer. One of 5 feet 4 inches, and weighing 

 nearly 50 lbs., was taken this summer in the mackerel- 

 nets off Deal. 



