238 FIELD MUSEUM OF NATURAL HISTORY ZOOLOGY, VOL. X. 



ff . Fins with spines. 



i. Body elongate, not very deep; dorsal fins 2, separate or more or 



less united; lateral line incomplete or wanting. 

 j. Scales large, dorsal fins well separated; caudal fin forked; ventral 



fins abdominal, far apart. Mugilida, p. 332. 



jj. Scales if present (present in all of the Panama species) moderate 



or small; dorsal fins separate or united; caudal fin rounded; 



ventral fins thoracic, close together or united to form a sucking 



disc. Gobiidce, p. 349. 



ii. Body deep, compressed; scales moderate; lateral line interrupted 



under base of dorsal, reappearing lower down on caudal peduncle; 



dorsal fin single, composed of spines and rays. Cichlidce, p. 338. 



