1st dorsal spine basal pterygiophore 



2nd dorsal spine 



Figure \19.—Alutera heudelotii 

 lateral view of head, 

 107 mm SL, Florida. 



preroric 

 hyomandibula 

 operculum 

 suboperculum 

 preoperculum 

 metapterygoid 



articular 



angular 



interoperculum 



symplectic 



mesopterygoid 



ectopterygoid 



Figure 120.— Psilocephalus barbatua: lateral 

 view of head, 137 mm SL, Singapore. 



170 



