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 water 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 Ibs., was taken this summer in the mackerel- 

 nets off Deal. 



