PERCID^, O.) 



h. Scales deciduous, 

 a. Th/" lateral line commencivg hcneafh the second dorsal. An 

 acute ridge from the eye extending backwards over the 

 operclea 43. Mickoiciitiiys 



j8. The lateral line commencing behind the head. 



aa. Teeth on the palatine bones. 



aa PrcBopercrdum with a double serrated ridge. The 

 first dorsal with six to seven, the anal with two 

 spines ; operculum spiniferous 44. Apogon. 



j3/3. Prceoperculicm with a double entire ridge. The 

 first dorsal with six, the anal with two spines ; 

 operculum spiniferous 45. Apooonichtiiys. 



hb. No teeth on the palatine bones. Eye very large. No 

 denticulations on the bones of the skull. Many 

 pancreatic caeca 48. Pomatomus. 



2. The spinous dorsal little developed. 



Scales minute, enveloped in the epidermis ; spines of the dorsal 



variable in number 32. Riiypticus. 



3. One dcyrsaljin. 

 a. With two <w three anal spines. 

 a. Pyloric appendages in small number, 

 aa. Operculum with a strong bony ridge. 

 Opercles denticulated ; scales small 29. Polyprion. 



bb. Operculum without bony ridge. 

 §. No teeth on the palatine bones. 



Opercles spiniferoufl ; the muciferous channels of the bones of 



the skull much developed ; scales rather small 9. Acerina. 



§. Teeth on the palattne bones. 



* Operculum spiniferous. 



** Scales moderate. 



t D. with 12-13 spines. Body rather elevated 35. Myriodon. 



t B. with 8 spines. Head entirely covered with 



scales , 38. Glaucosoma. 



** Scales small. 



t Operculum very strongly arm^d; prseoperculum 



with strongly serrated lower limb ; dorsal with 



nine spines. Known only from stuffed specimens, 33. Aulacocephalus. 

 t Operculum moderately armed ; praeopercixlum not, 



or obtusely serrated. Dorsal with eleven spines. 50. Oligouus. 



* Bones of the skull without any denticulations or spines. 



Dorsal with ten spines ; scales rather small 20. Apsilus. 



