2 7 



UTILITARIAN ZOOLOGY 



The Lemon Dab (P. microcephalus}. This is often sold under 

 the name of Lemon " Sole ", but it is a poor substitute for the true 

 Sole, which it resembles in shape though not in colour. The dark 

 side of the body is of a yellowish-brown, marked with numerous 

 spots. The range is practically the same as that of the Dab, but 

 it is most abundant in fairly deep water. 



THE MACKEREL FAMILY (SCOMBERID^:). The members of this 

 family are highly predaceous tropical and temperate fishes which 

 swim in shoals in the open sea, but approach the land in pursuit 

 of prey. Their form admirably adapts them to swift progression 

 (see vol. iii, p. 41). It will be necessary here to consider two 



Fig. 1197. Mackerel (Scomber vernalis] 



species, the Mackerel and Common Tunny, both of which lay 

 floating eggs. 



The Mackerel (Scomber vernalis, fig. 1197). This is one of 

 the most beautiful of our native marine fishes, and adults vary 

 in length from about i foot to 17 inches. The range is from 

 the Mediterranean to the Canaries, and north along the shores 

 of Europe to the south of Norway. So far as British fisheries 

 are concerned mackerel are of importance from the coast of 

 Norfolk round the Straits of Dover to Devon and Cornwall. 

 Drift-nets and seines are the chief means of capture, but lines are 

 also employed, especially in the south-west of England. 



The Common Tunny (Orcynns thynnus]. This can be de- 

 scribed as a gigantic mackerel, which may reach a length of 

 10 feet, and a weight of about half a ton. Although sometimes 

 taken in the North Sea and Baltic it is essentially a native of 

 the Mediterranean, where it has been the object of an important 



