lxii Field Columbian Museum — Zoology, Vol. V. 



11. Anal spines single; dorsal spines slender, page 



3 to 8 Atherinidce 165 



bb. Ventral fins present, thoracic or jugular, 

 m. Ventral fins each composed definitely of 

 one spine and 5 soft rays; eyes symmet- 

 rical, one on each side of the head, 

 n. Ventral fins completely united; gill mem- 

 branes joined to the isthmus; no lateral 



line Gobiidce 225 



nn. Ventral fins separate. 

 o. Nostril single on each side; lateral line in- 

 terrupted; anal spines 3 to 11 CichlidcB 204 



00. Nostril double on each side; lateral line 

 not interrupted, 

 p. Lateral line extending on caudal fin. 

 q. Anal spines 3, the second very strong, 

 r. Dorsal fins two, separate; preopercle 

 with two margins, the posterior one 



strongly toothed Centropomidce 198 



rr. Dorsal fins connected; preopercle with 



one margin Hcemulidce 199 



qq. Anal spines 1 or 2 Scicenidce 202 



pp. Lateral line, if present, not extending on 

 caudal fin. 

 s. Dorsal fins separate or scarcely con- 

 nected, 

 t. Anal spines 3; the second very strong; 



body elongate, compressed HcemuHdcF 199 



tt. Anal spines 1 or 2 ; body usually slender, 

 never much compressed. 

 u. No lateral line; ventral fins with the 

 inner rays the longest; dorsal spines 



8 or less Gobiidce 225 



uu. Lateral line present; ventral fins with 

 the outer rays the longest; dorsal 



spines 8 or more Percidce 196 



ss. Dorsal fin single, the spinous and soft 



portions being connected; body usually 



deep and much compressed. 



mm. Ventral fins each not composed definitely 



of one spine and 5 soft rays; eyes unsym- 



metrical, both being on the same side of the 



head Sole idee 234 



