OF THE BRITISH ISLANDS. 31 



tribe, is captured off our coasts throughout the year, while 

 at certain seasons it approaches the shores in prodigious 

 numbers, impelled by instincts connected with their breeding 

 habits, or in pursuit of the shoals of young Clupeidce, 

 Herrings, Pilchards, &c, upon which they in large measure 

 subsist. The gorgeous colouring of a Mackerel taken freshly 

 from the water almost defies description or reproduction 

 with the artist's brush. The dorsal region reflects the most 

 brilliant metallic shades of green and blue, intersected by 

 some three dozen narrow V-shaped bands, which pass 

 obliquely forwards towards the lateral line ; a single dark 

 stripe is usually developed from the pectoral fin along the 

 course of but a little beneath this line, while the whole 

 surface of the sides and abdomen below this point are 

 iridescent with every colour of the rainbow — purple, gold 

 and silvery shades struggling for the mastery. Sometimes 

 this lower region of the body is variegated with small spots 

 and blotches, while well-marked varieties, formerly re- 

 garded as distinct species, and described under the titles of 

 the " Scribbled " and " Dotted " Mackerel, have the more 

 customary dorsal bands replaced by a uniform series of 

 black dots or scribblings. These several varieties will be 

 found well represented among the preserved examples in 

 the Day Collection. From fourteen to sixteen inches is the 

 ordinary length of the common Mackerel, examples 

 measuring eighteen inches being of very rare occurrence. 

 Some idea of the abundance of this valuable food-fish may 

 be gained from the record, that as many as 300,000 were, in 

 May 1868, netted in one morning off the Scilly Isles. The 

 Spanish Mackerel {Scomber colzas), No. 35, much resembles 

 the common species, but grows to a considerably larger 

 size, and is only an occasional wanderer to our shores, 

 its headquarters being the Mediterranean. Among the 



