534 THE LITTLE DOG-FISH. 



The body of the Sturgeon is elongated, and slightly five-sided from 

 the head to the tail. Along the body run five rows of flattened bony 

 plates, each plate being marked with slight grooves in a radiating 

 fashion, and having a pointed and partly conical spine on each plate, 

 the points being directed toward the tail. The plates along the sum- 

 mit of the back are the largest. 



The fishes belonging to the next group have their gills fixed by their 

 outer edge to the divisions in the gill-openings at the side of the neck. 

 This group includes the Sharks and the Rays, many representatives of 

 which creatures are found on the British coasts. 



The first family of this large and important group is known by the 

 name of Scyllidse, and its members can be recognized by several distin- 

 guishing characteristics. They have spout-holes on the head, and the 

 gill-openings are five in number on each side. Sometimes there seem 

 to be only four openings, but on closer examination the fourth and 

 fifth are found set closely together, the opening of the fifth appearing 

 within that of the fourth. The teeth are sharp and pointed, and the 

 tail is long, notched on the outer side, and is not furnished with a 

 fin. 



One of the commonest British species is the Little Dog-fish, called 

 by several other names, as is usual with a familiar species that is found 

 in many localities. Among such names are Small Spotted Dog-fish, 

 Lesser Spotted Shark, Morgay, and Robin Huss. 



This fish is plentiful on our coasts, especially in the southern extrem- 

 ity of England, and is often thought a great nuisance by fishermen, 

 whose bait it takes instead of the more valuable fish for which the 

 hook was set. It generally remains near the bottom of the water, and 

 is a voracious creature, feeding upon crustaceans and small fish. It 

 often follows the shoals of migrating fish, and on account of that custom 

 is called the Dog-fish. Generally its flesh is neglected, but when prop- 

 erly dressed it is by no means unpalatable, and is said to be sometimes 

 trimmed and dressed in fraudulent imitation of more valuable fish. 



The skin of this and other similar species is rough and file-like, and 

 is employed for many purposes. The handles of swords, where a firm 

 hold is required, are sometimes bound with this substance, and joiners 

 use it in polishing the surface of fine woods, so as to bring out the grain. 

 It is also employed instead of sand-paper upon match-boxes. 



The egg of this species is very curious in form and structure, and is 

 often found on the seashore, flung up by the waves, especially after a 

 storm. These objects are familiar to all observant wanderers by the 

 seashore, under the name of mermaid's purses, sailor's purses, or sea 

 purses. Their form is oblong, with curved sides, and at each angle 

 there is a long tendril-like appendage, having a strong curl, and in 

 lorm not unlike the tendrils of the vine. The use of these appendages 



