1 82 MAMMALIA, REPTILIA, ETC. 



Only those acquainted with this fact can understand 

 the bitter hatred which fishermen in general entertain 

 for the dog-fish. When they catch it they will often put 

 it to all kinds of torture, as if in revenge ; and the fish 

 almost seems to know that it has to run the gauntlet 

 of its enemies, and therefore shows no mercy in re- 

 turn, if it can only obtain the chance to injure its foes. 

 It is very abundant off our shores, but we have not 

 heard of its being eaten, except off some parts of 

 the Lancashire coast, and we very much suspect that 

 this is done more from motives of revenge than 

 gustatory enjoyment ! The small-spotted dog-fish 

 (Scy Ilium canicida) is rarer, and of a more graceful 

 shape, so that it is a " stock " object in marine aquaria. 

 Many of these fishes, as well as the skates, have a 

 peculiar way of forming egg-cases, and these are very 

 interesting to the zoologist, because in some instances 

 they are so transparent that he can witness the entire 

 development of the contents through them. These 

 egg-cases may always be picked up on the beach, 

 especially those of the skates, which, on account of 

 their shorter tendrils, seem to be more easily detached 

 from the objects to which the fish originally fastened 

 them. These egg-cases are, however, usually found 

 empty. They go by the popular name of "pixy 

 purses." We give figures of those of the common 

 skate (Batis vulgaris), and of the smaller spotted dog- 

 fish (Scyllium canicula). The latter has very long, 

 pea-like, but hollow tendrils, which wind round the 



