FISHES 



285 



of the larger sharks. The Common Tope {Galeus cants) is a 

 small shark with a very wide distribution, and is a well-known 

 British species. It may attain a length of 6 feet or more, and 

 in colour is dark grey above and white below. The body is 

 slender and the snout prolonged and pointed. A somewhat 



CAUDAL FIN 



VeHTBAU FIN 



Fig. 166. — Sharks, reduced to various scales 



A, Spotted Dog-Fish {Scylliutn canicula). b, Blue Shark [Carcharias glaucus), 

 c, Hammer-headed Shark {Zygeetta malleus). 



smaller form, common in British seas and widely distributed over 

 the world, is the Smooth Hound {Mustelus Icevis), which can 

 easily be distinguished from the Tope by its blunter snout, and 

 the presence of whitish spots on the back. The most remarkable- 

 looking member of this family is undoubtedly the Hammer-headed 

 Shark {Zygcena malleus), in which, as the name indicates, the head 

 is broadened out like a T by the presence of projections upon 

 which the eyes are situated. It has occasionally been taken in 



