426 



Survey of Fishing-Grounds, West Coast of Ireland, 1890—1891. 



that respect immature. We are not in a position to affirm any exact size at which 

 the elongation of the dorsal commences in either species, and, no doubt, in this 

 respect there is considerable variation ; but amongst the examples before us a male 

 of C. maculatus is fully mature at 4^- inches, whereas the smallest male of C. lyra 

 which exhibits any (external) approach to maturity is 4-|- inches long. There is 

 thus a possibility, in so far as concerns the elongation of the dorsal, of confusion 

 between a mature female of C. maculatus and an immature male of C. lyra, to avoid 

 which, in the absence of any very well-marked differences in colouration, a some- 

 what close inspection of minor characters is necessary, and we believe that the 

 subjoined Table of dimensions and remarks will be found of use. 



C. maculatus. (Adult.) 



Male. 



Female. 



Length of head to total length without 



caudal fin, 1 to 3J 



Horizontal diameter of eye to length of 



head, 1 to 3J- 



Length of snout (exclusive of protractile 

 mouth) to horizontal diameter of 

 eye, H to 1 



"Width of interorhital space to horizontal 



diameter of eye, . . . . 1 to 5 ca. 



Anterior dorsal ray elongated, reaching 

 the middle of second dorsal. 



Length of head to total length without 



caudal fin, 1 to 3i 



Horizontal diameter of eye to length of 



head, . . . . . 1 to 2J 



Length of snout (exclusive of protractile 

 mouth) to horizontal diameter of 

 eye, . . . . . . 1 to IJ 



Width of interorhital space to horizontal 



diameter of eye, . . . . 1 to 6 ('a. 



Anterior dorsal ray not elongated. 



The second dorsal fin of the adult male is considerably higher in C. maculatus 

 than in C. lyra. In a specimen of the former, 4^ inches long, the first ray of the fin 

 mentioned is contained not quite 3 times in the total length, without the caudal. 

 In three specimens of C. lyra, exhibiting the full development of the first dorsal, 

 and measuring respectively 4|-, 7\, and 9 inches, the same ray is contained 5f , 5, 

 and 6 times in the total, without the caudal. In males of both species, according 

 to Lilljeborg's description and our own experience, the second dorsal fin is highest 

 posteriorly, although Day's figure of tlie male C. maculatus shows this fin highest 

 in front. It is of about equal height throughout in females of both species. The 

 first ray of the first dorsal in fully adult males of C. lyra extends back as far as the 

 caudal, but of course intermediate stages occur, necessitating a recourse to other 

 characters for specific determination. Such are furnished by the proportions of 

 the eye and snout, which differ considerably in the two species, since in the adult 

 male C. lyra the horizontal diameter of the eye is contained 2^, in the adult 

 female \\ times in the length of the snout (exclusive of the protractile mouth 



