107 (fl). COTTID.E. 680 



and sliores of northern regions ; many species found in fresh waters. 

 The group, as here understood, comprises a considerable variety of 

 forms, and is very difficult to define, as it grades into the Liparididcv 

 on the one hand, and into the Scorpcenidce on the other. Most of the 

 species are of small size and singular aspect, and none are valued as 

 food. The genera have been probably too much multiplied, and sev- 

 eral of them can be only provisionally accepted. 



(TrigUflcc, group Cottina, pt.; group Scorpcenina, part, Giinther, ii; family Psychro- 



lutldai Giinther, iii, 516, 517.) 







a. Spiuous dorsal longer than soft part, of more than 14 spines. (Hemitripterinas.) 

 b. Spiuous dorsal deeply notched, the anterior spines highest; skin rough, with 



prickles and tubercles ; teeth on vomer 

 and palatines; gill-membrane free from 

 isthmus; no slit behind last gill. 



HEMITRIPTERUS, 361. 



aa. Spinous dorsal shorter than soft part, of less than 13 spines, 

 c. Ventral tins wanting. (Ascellchtkyince.) 



d. Skin naked; no slit behind fourth gill; gill-membrane free from isthmus; 



teeth on vomer and palatines. 



ASCELICHTHYS, 362. 



cc. Ventral fins present. 



e. Spinous dorsal little deA r eloped, continuous with the. soft dorsal, the spines 



slender, concealed in the loose naked 

 skin; gill-membranes broadly joined to 

 the isthmus ; no slit behind last gill. 

 (Psychroluiinoe.) 



f. Vomer and palatines toothless PSYCHROLUTES, 363. 



ff. Vomer with teeth CorruNCULUS, 364. 



ce. Spinous dorsal not concealed. 



g. Gill-openings extending below at least to the base of lowest pectoral 



ray. (Cottinoe.) 



h. Slit behind last gill obsolete * ; vomer with teeth. 

 i. Gill-membranes broadly united to the isthmus, not forming a fold 

 across it ; head feebly armed ; palatine teeth few or none. 



URAXIDEA, 366. 

 ii. Gill-membranes free from isthmus, or else forming a broad fold 



across it; head well armed. 

 j. Palatine teeth well developed; body usually more or less 



scaly ICELUS, 365. 



jj. Palatine teeth none ; body without true scales COTTUS, 367. 



hh. Slit behind last gill evident. 



Jc. Vomer without teeth ; preopercular spine with antler-like pro- 

 cesses; gill-membranes forming a fold 

 across isthmus ... GYMNACAXTHUS, 368. 

 Jck. Vomer with teeth. 

 I. Skin not hispid, t 



* A round pore in some species of Cottus, 

 t Partly villous in Triglops. 



