PORBEAGLE GROUP. 525 



the young than in the adult. Feeding on molluscs and crustaceans, this species 

 (which ranges over most warm seas) produces about a dozen young at a birth, 

 these being attached by a placental structure to the walls of the uterus of the 

 parent. Curiously enough such connection is, however, totally wanting in the 

 young of the other British species (M. vulgaris). In habits the hounds are bottom- 

 haunting species, as indeed might be inferred from the nature of their food. On 



SPINY DOG-FISH AND SMOOTH HOUND (i nat. size). 



the English coast the smooth hound generally makes its appearance during the 

 summer in pursuit of the shoals of pilchard and herring. Several other genera of 

 this family must be passed over without notice. 



The Porbeagle Group, — Family Lamnidje. 



Agreeing with the typical sharks in the position of the two spineless dorsal 

 fins, the members of the present family may be distinguished by the absence of a 



