OF SCOMBER PUNCTATUS WITH S. SCOMBEE. 147 



Fauna ' (1807), adds the " Spanish Mackerel " (S. colias) which is 

 likewise included by Jenyns, ' British Vertebrate Animals' (1835), 

 Yarrell, 'History of British Fishes' (editions 1836 and 1841), 

 "White, ' Catalogue of British Fishes (1851),' and Thompson, 

 'Natural History of Ireland (1856)— the last three authors con- 

 sidering S. maculatus, Couch (Mag. Nat. Hist. v. p. 832), as a 

 synonym of S. colias. Sir John Richardson, in the 3rd edition of 

 Yarrell's ' British Fishes,' included 8. punctatus, Couch, as a 

 distinct species, observing, at the same time, that, " as no second 

 example has yet been met with, and the chief peculiarities in the 

 Dotted Mackerel are its colours and markings, its specific rank 

 may remain a question until the acquisition of other specimens 

 furnish the means of investigating its internal structure." Dr. 

 Giinther, ' Catalogue of the Fishes of the British Museum,' 1860, 

 places the S. punctatus among the doubtful sjjecies upon which 

 no opinion is offered ; while S. scriptus, Couch, which may prove 

 to be merely another variety of the Common Mackerel, had not 

 been described at that period. 



Couch's example of the Dotted Mackerel (S. punctatus) was 

 a female, 15 '5 inches in length, captured in a mackerel-seine at 

 Looe, in Cornwall, July 6th, 1848. It was erroneously said to 

 possess an air-bladder, which, however, Couch, in his ' Fishes of 

 the British Islands ' (1863), observes was a mistake of Sir John 

 Richardson's, the specimen having been "destitute of a swimming- 

 bladder." He considered that it differed from the common 

 Mackerel in that there " were scales which covered the surface 

 of the sides and belly, where none at all appear in the common 

 species." The example of the common species under that author's 

 eye at the time appears to have been thickly covered with mucus ; 

 as in the specimens I have examined scales were present " on the 

 sides and belly;" consequently, in this respect, no difference 

 exists between the two forms. Next Couch draws attention to 

 the length of the interspace between the dorsal fins in the two 

 forms ; but if a pair of proportional compasses is employed, it will 

 be found that distance is identical in the two figures given in the 

 ' History of the Fishes of the British Isles.' In short, Couch 

 justly concludes that " the most remarkable distinction between 

 this and the other British species of Mackerel was in the colour, 

 which was of an uniform dark neutral tint over the head and back, 

 without any bands or variegations ; it might be termed an olive 

 bluish-green, with green reflections at the sides ; and from before 



