317 



Order III. ANACANTHINI. 



Vertical and ventral fins without spinous rays* 

 The ventral fins, if present, are jugular or thoracic. 

 Air-bladder, if present, without pneumatic duct. 



Cfr. MUller, in Berl. Abhandl.' 1844, p. 174. 



Si/nojpsis of the Families. 



A. ANACANTHINI GADOIDEI. 



Structure of the head symmetrical. 

 The smaller portion of the dorsal and 



anal fins is formed by spines 1. GadopsidaB, p. 318. 



Gill-opening narrow, the gill-membranes* 



being attached to thfi isthmus. Ver- 

 tical fins confluent into one 2. Lycodidae, p. 319; 



Gill-openings wide, the gill-membranes 



not attached to the isthmus. Ventral 



fins composed of several rays, or, if 



they are reduced to a filament, the 



dorsal is divided into two. Either the 



caudal free from dorsal and anal, or, if ' 



the vertical fins are united, the dorsal 



with a separate anterior portion. Rays 



of the second dorsal well developed . . 3. Gadidae, p. 326. 



Gill-openings wide, the giU-membranes 

 not attached to the isthmus. Ventral 

 fins rudimentary (reduced to a fila- 

 ment), or absent, jugular f. No sepa- 

 rate anterior dopsal. Caudal generally 

 united with dorsal and anal 4. OphidiidaQ, p. 370. 



A separate anterior dorsal ; the second 

 continued on to the point of the tail, 

 and composed of very feeble rays. 

 No caudal fin. Ventrals composed of 

 several rays, jugular or thoracic. ... 5. MacmridaB, p. 390. 



* With the exception of Gadopsis, p. 318. Except in Brotulophis. 



