30 MARINE AND FRESHWATER FISHES 



water ; and the smaller form, rarely exceeding the dimen- 

 sions of four or five inches, occurring abundantly close 

 to land. 



Among the titles by which the last-named form is 

 locally recognised may be mentioned those of the Adder- 

 Pike, Black-fin, and Sting-fish ; that of the Cat-fish and 

 Sting-bull being applied in a like manner to the larger 

 variety. The colours in the two species closely correspond, 

 consisting of a grey or yellowish ground-tint, darkest on 

 the back, and ornamented on the sides by numerous oblique 

 lines of blue, brown, and yellow ; the spinous dorsal fin, as 

 a marked contrast in both types, being an intense black — 

 this last-named peculiarity is well shown in the spirit- 

 preserved examples in the Day Collection. 



FAMILY IX.— The Mackerel Tribe {Scombridce). 



Body usually elongated, spindle-shaped, slightly com- 

 pressed, naked or covered with minute scales ; teeth well 

 developed, pre-operculum without a bony stay, the bones of 

 the head not armed with defensive spines ; dorsal fins two 

 in number, the second one and also the anal fin, usually 

 separated posteriorly into a number of minute finlets ; 

 branchiostegal rays seven or eight in number ; an air-bladder 

 present or absent. 



The members of the Mackerel tribe, as edible fishes, take 

 equal rank with those of the Herring and Cod families, and 

 are accordingly made the subject of special notice in the 

 Handbook devoted to the food species. All are of 

 essentially pelagic habits, abounding, usually in shoals, 

 throughout the Temperate and Tropical seas, and subsisting 

 on other marine fishes. The common Mackerel (Scomber 

 scomber), No. 34, which may be taken as the type of its 



