185 



I propose the name of Acanthocottus, for the marine 

 species, which are generally of a larger size than those 

 found in fresh water.* They are characterized by having 

 spines upon each of the opercular bones. The preoperculum 

 itself has several always strongly developed. The surface of 

 the head, and also often the circumference of the orbits, are 

 either armed with spines, or else they are serrated or notched in 

 different ways. The nasal bones are also in most of the species 

 surmounted by a spine or ridge. The head itself is rather higher 

 than broad ; sometimes much deformed, with proportionally very 

 large eyes, and a deep occipital depression. The mouth is always 

 more deeply cleft than in the fresh water species, but the denti- 

 tion, as a whole, is nearly the same. Nostrils double, distant 

 from each other, tubular, the anterior being much larger, the 

 posterior close to the orbit. The body is scaleless ; the back 

 is often arched, and the first dorsal fin almost as high as the 

 second. Some species have three, others four, soft rays to the 

 ventral fins. The lateral line runs uninterrupted from the head 

 to the base of the caudal fin. 



The American species of this genus are the following : — 



Acanthocottus Grcenlandtcus Grd. — Cottus Grcenlandicus 

 Cuv. & Val. Hist. Nat. Poiss. iv. 1829, p. 185. — Rich. 

 Faun. Bor. Amer. iii. 1836, p. 46, and Add. p. 297, 

 PL 95, fig. 2. — Storer Rep. 1839, p. 16. — DeKay, 

 New York Fauna, 1842, p. 54, fig. 10. — Storer, Synops. 

 1846, p. 53. Cottus quadricornis Sabine, App. to Parry's 

 First Voy. 1821. Cottus scorpius Fabr. Faun. Groenl. 1780, 

 p. 456. Cottus variahilis Ayres, Proc. Best. Soc. Nat. 

 Hist. I. 1842, p. 68, and Bost. Journ. of Nat. Hist. iv. 

 1843, p. 259. (Young) — Greenland; Cuvier and Valen- 

 ciennes. — Davis Strait ; Richardson. — Maine and Massa- 

 chusetts ; Storer. — Connecticut ; Ayres. — Hellgate (N. 

 Y.) ; DeKay. 



Acanthocottus scorpioides Grd. — Cottus scorpioides Fabr. 

 Faun. Groenl. 1780, p. 157. — Cuv. & Val. Hist. Nat. 

 Poiss. IV. 1829, p. 187. — Richards. Faun. Bor. Amer. 



* "With the exception of C. polaris ; but the specimens which have been ob- 

 served may not have been full-grown. 



