Mr. W. Thompson on a new British Fish. 411 



as a compliment well merited by Mr. Couch for his practical 

 knowledge of fishes, that the genus be named after him, 

 Couchia. To the Strangford species the name of minor may- 

 be given. 



Generic characters. — Couchia. Body elongate, compressed 

 posteriorly : first dorsal fin, hke that of Motella, very low, 

 composed of soft rays unconnected by a membrane : pectorals 

 and ventrals placed high : second dorsal and anal fin long : 

 divisions of opercle well defined exteriorly. 



Specific characters. — Couchia minor. (Plate XVI. fig. 1.) 

 Lesser Mackerel Midge. Upper jaw the longer: ventrals 

 long (from ^ to ^th the length of head), and black at their 

 termination: sides silvery*. 



The Gadus argent eolus (PI. XVI. fig. 2.) of Montagu 'Wern 

 Mem.*, V. ii. p. 449. must be adverted to in connexion with the 

 present species. By its describer, it is stated to be " nearly 

 allied to the three-bearded Cod, Gadus Mustela, in most par- 

 ticulars ; but the shape of the head and the colour f are essen- 

 tially difierent.*' It was the striking dissimilarity presented 

 by a comparison of specimens of C. glauca and Mot. quinque- 

 cirrata in these very characters, that led me to re-separate 

 them generically ; and consequently the C. glauca and G. ar- 

 genteolus may, from agreement in these points, be in the first 

 place regarded of the same genus J as here defined. On 



I know not whether this term itself has been used, appears, from Jourdan's 

 ' Diet, des Termes,' &c., to have been adopted in a somewhat similar sense 

 by four different authors. 



* The absence of cirri is not given as a character, as better vision than 

 mine may yet detect them. 



+ The name of Whitebait {Clupea alba), which Montagu mentions as ap- 

 plied to the G. argenteolus by the fishermen, hoAvever erroneously, is suffi- 

 ciently indicative of its Clupea-like aspect. 



+ Montagu remarks of the G. argenteolus, that " the whole fish is of a 

 silvery resplendence except the back, which is blue changeable to dark 

 green ; " and that the three-bearded Cod he has " taken of all sizes, from 

 the most minute to its full growth of 16 or 17 inches, and never ob- 

 served it to vary in colour, except as it grows large it becomes more rufous, 

 and throws out spots, which is never observed till it exceeds 6 or 7 inches, 

 but is invariably rufous-brown in its infant state." As a general descrip- 

 tion, this is equally applicable to the five-bearded Cod (A/ot. quinquecirrata), 

 of which I have however taken spotted examples smaller than has been just 

 noticed. Specimens now before me of different sizes, from 1^ to 5^ inches 

 in length, are of a tolerably uniform brown colour on the head, back, sides 

 and fins, varied only in the larger individuals by yellowish white at the an- 



