218 PISHES. 



h. No teeth on vomer or palatines ; mouth small, contracted, 

 subinferior ; head short and thick, with swollen cheeks ; 

 spinous dorsal rather long ; maxillary non-protractile/ 

 anal spines strong ; body elongated, little compressed. 



DiPLESIUM, 9. 



Kk. Vomerine teeth present ; dorsals contiguous, but distinct ; 

 the spinous dorsal short; max. protractile; the mouth 

 rather small, horizontal, subinferior. 

 *'. Anal spines two, well developed ; the first the longer. 



Ulocbntba, 10. 

 a. Anal spines obscure and undiflferentiated from the soft 



rays Boleosoma, 11. 



gg. Upper jaw not protractile. 

 j. Gill membranes broadly connected across breast ; 

 scales large ; cheeks and opercles scaly ; mouth small, 

 horizontal, subinferior (as in Boleosoma); caudal pe- 

 duncle rather slender. . . . Nanostoma, 13. 

 jj. Gill membranes nearly free ; body rather short, 

 deep, strongly compressed ; scales small ; cheeks naked ; 

 mouth rather large, oblique (as in PceeiUchthys) ; caudal 



peduncle deep Nothonottjs, 13. 



'** Lateral line incomplete or wanting; no ventral plates; upper 

 jaw not protractile; second dorsal larger than anal; vomer 

 with teeth. 

 k. Lateral line present on anterior part of body; anal spines 

 two. 

 I. Lateral line nearly straight 

 m. Spinous dorsal fin well developed, two-thirds or more 

 the height of the second ; the spines graduated, never 

 ending in little fleshy knobs ; lateral line extending 

 more than half the length of the body ; mouth moder. 

 ate, the upper jaw usually a little the longer; gill 

 membranes free. . . . Pcecilichthys, 14. 

 mm. Spinous dorsal low and small, the spines subequal, 

 scarcely half the height of the soft rays, in males end- 

 ing in little fleshy knobs; gill membranes connected; 

 body elongated, compressed. . Etheostoma, 15. 



