6 
actinopterygii. 
temporal bone scales cycloid, 
regularly arranged ateral line 
above middle of flank Notacanthid® (p. 168). 
Premaxilla completely excluding 
maxilla from margin of upper- 
jaw ; opercular apparatus com- 
plete ; scapular arch supported 
by post-temporal bone: body 
with paired longitudinal series 
of scutes ; lateral line piercing 
a series of scutes above middle 
of flank Dercetid® (p. 171). 
(6) Supraoccipital separating the parietal 
bones in the middle line ; squa- 
mosal bones much reduced, and 
pterotic region prominent. 
Maxilla partly entering gape ; upper 
dentition chiefly on inner bones 
of mouth ; abdominal vertebrae 
without transverse processes; 
an adipose dorsal fin; scales 
minute or absent, but usually 
rows of scutes, the dorsal series, 
when present, being unpaired. . Enchodontid® (p. 189). 
Premaxilla completely excluding 
maxilla from margin of upper 
jaw; dentition usually feeble, 
but upper enlarged teeth, when 
present, on the premaxilla; ab- 
dominal vertebrae without trans- 
verse processes; an adipose 
dorsal fin scales usually pre- 
sent, no scutes Scopf.lid® (p. 236). 
Premaxilla delicate but completely 
excluding relatively large max- 
illa from margin of upper jaw ; 
dentition absent or on inner 
bones; abdominal vertebra: with 
transverse processes; no adipose 
dorsal fin ; dense regular squa- 
mation 
Premaxilla completely excluding 
maxilla from margin of upper 
jaw ; dentition feeble or absent • 
abdominal vertebrae with trans- 
■ • verse processes ; paired fins ex- 
cessively enlarged 
Premaxilla small, and maxilla form- 
Gonorhynchid® 
[(p. 271). 
Chirothricid® (p. 279). 
