FAMILIES OF ACANTHOPTERI. 399 



t Mouth nearly vortical ; at a! fin long ; 

 whole head closely scaly. 



PRIACANTHID.E, 80 (6). 

 tt Month nearly horizontal ; anal fin 



rather short SERRANID.E, 86. 



WW. Maxillary with its upper edge for its 

 whole length slipping under the 



preorbital SPARID^E, 8H. 



ER. Anal fin elongate ; pscudobranchioe present ; 



spinous dorsal little developed. 

 X. Dorsal spines present : skeleton well 



ossified. 



Y. Pectoral fins broad, procurrent for- 

 wards. 



t Body scaly ; slit behind fourth gill 

 small; eyes superior. 



URANOSCOPID^E, 103. 

 ttBody naked; eyes lateral. 



TRICIIODONTID.Z, 10;*. 

 YY. Pectoral fin narrow, not procur- 

 rent; body scaly. 



LATILID/E, 101 (&). 



XX. Dorsal spines obsolete ; skeleton 

 more or less cartilaginous. 



ICOSTEHXE, 101. 

 GG. Gill-membranes united to the isthmus, restricting the gill-openings 



to the sides. 



Z. Body not elevated ; lateral line 

 obsolete; spinous dorsal short and 

 weak ; inner rays of ventrals long- 

 est GOBIID.E, 104. 



ZZ. Body elevated; lateral line 

 present; spinous dorsal well de- 

 veloped (Chcetodonliform fi-shes.) 

 a. Teeth setiforin, in many rows ; 

 vertical fins densely scaly ; tail 

 unarmed. 

 6. Dorsal fin divided. 



EPHIPPID^E, 97. 

 66. Dorsal fin continuous. 



CH/ETODONTID.E, 98. 

 aa. Teeth incisor-like, in one 

 row ; tail with 1 or more 

 spines on each side. 



ACANTHUKID.E, 99. 

 FF. Lower pharyugeals united. (Pharyngoynathi.) 



c. Nasal openings single on each side; scales mostly ctenoid. 



(1. Gills Hi, last slit small or obsolete ; pseudobranchia? present; anal 



spines 2 POMACKNTRID/E, 90. 



dd. Gills 4, a slit behind the last; pseudobranchine obsolete; anal 



spines 3 or more.. .CICHLID^E, 95. 



cc. Nasal openings 2 on each side; anal spines 3; scales mostly cycloid. 

 e. Viviparous; dorsal fin with a scaly sheath; anal rays slender and 



numerous EMBIOTOCUWE, 93. 



ee. Oviparous; anal rays rather few. 



