Thirteentli division : Acanth. centrisciformes. 



Two dorsal fins, the spinous short, the soft and the anal of mode- 

 rate extent. Ventral fins truly abdominal, imperfectly developed. 



One family only 4-i. Centeisced^, iii. p. 518. 



Fourteenth, division : Acanth. gobiesociformes. 



No spinous dorsal ; the soft and the anal short, or of moderate 

 length, situated on the tail ; ventral fins subjugular, j^, with an 

 adhesive apparatus between them or entirely absent. Body naked. 



I. An adhesive apparatus between the ventrals. 



42. GoBiEsociDJE, iii. p. 489. 



II. Ventrals none 43. Psychroltjtidje, iii. p. 516. 



Fifteenth division : Acanth, channiformes. 



Body elongate, covered with scales of moderate size ; no spine in 

 any of the fins ; dorsal and anal long. No superbranchial organ, 

 only a bonj' prominence on the interior surface of the epitympanic 

 bone. 



One family only 39. Ophiocephalid^, iii. p. 468. 



Sixteenth division : Acanth. labyrinthibranchii. 



Body compressed, oblong or elevated, with scales of moderate size. 

 A superbranchial organ in a cavity accessory to that of the gUls, for 

 the pui-pose of retaining water. 



I. Dorsal or anal sj^ines present, sometimes in great number. 



35. Labteinthici, iii. p. 372. 



II. Neither dorsal nor anal spines. 



36, LuciocEPHAxn)^, iii. p. 390. 



II. 

 Dorsal and anal fins developed. Vent in front of the ventrals. 

 Only one family 4. ApnEEDOi)EEiD.a:, ii. p. 271. 



III. 



Body riband-shaped, with the vent near its extremity ; a short 

 anal behind the vent ; dorsal as long as the body. 



Onlv one familv 28. Lophotid^, iii. p. 312. 



