196 PISCES. 



Those that inhabit fresh water have a nearly smooth head, and but one 

 spine to the preoperculum ; their first dorsal is very low. The most common 

 species is 



C. gobio, Lin. (The River Bull-head.) A small blackish fish, four or five 

 inches in length. 



The salt water species are more spinous, and when irritated their head 

 becomes still more inflated. Such is 



C. scorpius, Lin. (The Father-Lasher.) Three spines on the preoper- 

 culum. 



Other groups have lately been observed, which are partly allied to Cottus 

 and partly to Scorpsena. One of them is the 



HEMITRIPTERUS, Cuvier. 



The head depressed, and two dorsals as in Cottus ; no regular scales on the 

 skin, but teeth in the palate. The head is bristly and spinous, and has several 

 cutaneous appendages. The first dorsal is deeply emarginate, a circumstance 

 which has led some authors to believe they had three. 



But one species is known, which is from North America, Coitus tripterygius, 

 which is taken along with the cod. From one to two feet long, tinged with 

 yellow and red, varied with brown. 



SCORP^ENA, Linnaeus. 



The head, like that of a cottus, mailed and roughened, but compressed on 

 the sides ; body covered with scales ; several rays in the branchiae, and but a 

 single dorsal. If we except the armature of the cheek, and the tubercles, 

 which frequently give them an odd appearance, they closely approximate to 

 certain Percoides, such as the Acerinse and the Centropristes ; but though the 

 inferior rays of their pectorals, as in Cottus, are articulated, they are simple 

 and not branched. 



The remaining genera allied to or separated from Scorpsena are Pterois, 

 Blepsias, Apistus, Agriopus, Pelor, Gusterosteus (Stickle-backs of Europe), 

 and the 



MONOCENTRIS, Schneider. 



A singular genus; the body is short, thick, and completely mailed with 

 enormous angular, rough, and carinated scales ; four or five stout free spines 

 upply the place of the first dorsal ; each ventral consists of an immense 

 spine, in the angle of which a few soft and almost imperceptible rays are 

 concealed ; head bulky and mailed ; front gibbous ; mouth large ; shor 

 crowded teeth in the jaws and palatines, but none in the vomer ; eight rays in 

 the branchiae. But one species is known, the 



Jf on. japonica, Bl. Schn. Six inches long, of a silvery white. From the 

 sea of Japan. 



After this family we place the 



