202 riSHES. 



III. With two or more free spines in place of first dorsal ; ventrals 

 sub-abdominal, of a stout spine and a small ray; small fishes 

 scaleless or with bony plates. . Hemibbanchii, page 209. 



IV. Dorsal fins two, distinct, small, the first of 4 to 7 spines ; ven- 



trals abdominal; teeth feeble or wanting; scales cycloid, 

 silvery Pbbcbsocbs, page 208. 



V. With the first rays of the dorsal, or the whole first dorsal, of 



simple — usually stiff spines; first ray of ventral usually 

 inarticulate (spinous dorsal forming a hump in OydUypterus ; 

 a lamellated sucking disk in Beheneu, etc., wanting altogether 

 in AspidopJwroides and Qdbiesox). Acauthopteki, page 303. 



VI. Fin rays soft and articulated (excepting occasionally one or 



two in dorsal or anal) ; no ventral spines ; scales when pres- 

 ent, usually cycloid. 



* Ventrals jugular; dorsal and anal long, often divided. 



Anacauthini, page 208. 



** Ventrals abdominal. 



f Mouth entirely toothless ; abdomen not serrated ; lower 

 pharyngeals falciform, tooth-bearing; no adipose fin; 

 head naked ; fresh water. . Evbnto&nathi, page 311. 



f f Body elongated, scaly ; a series of keeled scales along sides 

 of abdomen ; lower pharyngeals united (as in Labridce) ; 

 no air duct; no adipose fin; no ventral serratures ; one 

 or both jaws or else pectoral fins greatly elongated; 

 chiefly marine. . . Synbntognathi, page 209. 



f ff Head more or less scaly (naked in Amblyopsis, the Cave 

 Blind Fish) ; both jaws fully provided with teeth ; lower 

 jaw usually longest; dorsal far back, nearly opposite 

 anal; no adipose fin, ventral serratures, nor peculiar 

 scales ; chiefly fresh water. . Haplomi, page 309. 



tttt Soft -rayed fishes showing none of the above combina- 

 tions of characters ; head naked ; adipose fin or abdominal 

 serratures often present; dentition and habitat various. 



IsospoNDTLi, page 210. 

 *** Ventrals entirely wanting. 



:|: Jaws with teeth; vent at the throat; body oblong; cave 



fishes Haplomi, page 209. 



^;j: Jaws toothless; vent normal; body serpentiform. 



Ahaoanthini, page 208. 



