76 WITH HARD CHEEKS. 



ACANTHOPTERYGII. WITH HARD CHEEKS. 



THE ROUGH-TAILED STICKLEBACK. 



BANSTICKLE, SHARPLIK. Scotland. 



Gasterosteus trachurus, Cuv. et VALENC. Hist. Nat. des Poiss. t. iv. p. 481, 



pi. 98, fig. 1. 



,, aculeutus, BLOCH, pt. ii. pi. 53. fig. 3. 



,, ,, DONOVAN, pi. 11. 



Generic Characters. Body without scales, more or less plated on the sides ; 

 one dorsal fin, with free spines before it ; ventral fin with one strong spine, and 

 no other rays ; bones of the pelvis forming a shield, pointed behind ; branchi- 

 ostegous rays 3. 



THE ROUGH-TAILED THREE-SPINED STICKLEBACK is 

 one of the smallest as well as one of the most common 

 of our fishes, and is found both in the salt and in the 

 fresh water : not only does almost every river, brook, and 

 lake produce this well-known species, but it is also 

 common all round the coast from the Land's End to the 

 Orkneys. 



Cuvier and Valenciennes first noticed that three species 

 of Three-spined Sticklebacks had been constantly included 

 under the term G. aculeatus of Linnseus ; and the distin- 



