COMPENDIUM OF GENERIC DISTINCTIONS. 



779 



Sup-section. RAT I Body flat; spiracles. Gill-apertures 

 five, set before ventrals and under pectorals. 



Family. PRISTINID^E. Snout prolonged into a saw-like 

 form, with teeth on each edge. Skin covered with mosaic 

 scales. 



Genus. PRISTIOPHORUS. Beak with hooked spines of vari- 

 ous lengths, prickles attached to skin. Long barbel under 

 snout, and a keel on either side. Australasian seas. 



Genus. PRISTIS. Teeth of saw straight, similar, and some 

 what lancet-shape. Teeth flat and mosaic. Tail-fin short. 

 Many warm seas. 



Family. RAID/E. Body very flat and broad, with slender 

 tail. 



Genus. TORPEDO. Disc round and blunt in front ; back 

 rounded and naked; tail-fin three-cornered. Teeth pointed 

 and attached to a cartilage. A row of tooth-like projections on 

 edge of spiracles. Warm and temperate seas. 



Genus. RAIA. Snout pointed and keeled, disc broad, tail 

 very slender. Teeth mosaic-like ; in males pointed during 

 breeding season. 



Genus. TRYGON. Tail armed with one or more barbed 

 spines, and as long or longer than the body. Teeth either 

 pointed or wrinkled in the middle. Most seas. 



Genus. MYLIOBATIS. Teeth large, six-sided, mosaic. Tail 

 very long, slender, and with a powerful spine. Nostrils close 

 together in middle of snout. Warm seas. 



Genus. CBPHALOPTERA. Mouth at end of snout, and very 

 broad ; teeth small, flat, and leaf-like in lower jaw ; none in the 

 upper. Head with horn-like projections of the fins. Tail 

 very long, and with a spine. Many seas. 



Order. ACANTHOPTERYGII. Part of the rays of the 

 dorsal, ventral, and anal fins not jointed, and forming spines. 



Family. GASTEROSTEID/E. Body long and rather 

 compressed ; teeth in both jaws, not on tongue or palate. 

 Three branchiostegals (i.e. the slender curved bones by means 

 of which the gill-aperture is closed). Bones of operculum (or 

 gill-cover) not armed. Parts of skeleton forming external 

 armor. Scales none, or in plates along side. Single spine 

 before dorsal fin, and ventral armed with a strong spine, and 

 sometimes a short ray. 



Genus. GASTEROSTKUS. As family. Rivers and brackish 

 waters of cool latitudes. 



Family. BERYCIDyE. Body rather deep and com- 

 pressed ; eyes large and lateral. Slender teeth in both jaws, 

 often on palate. Branchiostegals, four or eight. Bones of 

 operculum armed. Scales, rarely bony, ctenoid (i.e. with 

 comb-like edge), or wanting. Ventrals under breast. 



Genus. MONOCENTRIS. Scales forming a bony mail, a few 

 isolated spines before dorsal. Seas of Japan. 



Genus. HOPLOSTETHUS. Abdomen notched. No teeth on 

 vomer. One dorsal. Mediterranean. 



Genus. MYRIPRISTIS. Two dorsals. No prasopercular 

 spine (see page 197). Indian seas. 



Genus. HOLOCENTRUM. Two dorsals. Prasopercular. 

 spine. Upper jaw not projecting. Asiatic seas. 



Family. PERCIDvE. Scales ctenoid, lateral line mostly 

 continuous. Operculum armed. Branchiostegals, seven or 

 eight. Teeth large, pointed, on jaws, palate, and vomer. 

 Dorsal with spiny and soft portion ; ventrals under breast, 

 with one spine and five soft rays. 



Genus. ' PERCA. Dorsal with thirteen to fifteen spines. 

 Praeoperculum and prseorbital (i.e. the bone before the orbit of 

 the eye) notched ; head naked above ; scales small. Many 

 fresh waters. 



Genus. LABRAX. Dorsal, nine spines. Teeth on tongue ; 

 prasoperculum toothed beneath. Many seas. 



Genus. ACERINA. No bony ridge on operculum, no teeth 

 on palatine bones. Opercula armed ; scales small. Many 

 fresh waters. 



Genus. LUCIOPERCA. Two dorsals, two spines on anal. 

 Dorsal spines twelve to fourteen. Operculum armed, praeoper- 

 culum notched. European rivers and lakes. 



Genus. CBNTROPOMUS. Body flattened, operculum not 

 spined. North America. 



Genus. CBNTROPRISTIS. One dorsal. Canine teeth very 

 small ; teeth on vomer in angular or triangular patch. Oper- 

 culum spined, prseoperculum serrated. North America. 



Genus. SERRANUS. Scales small, teeth on palatine bones. 

 Dorsal nine to eleven spines, anal with three. Operculum 

 spined. Many warm seas. 



Genus. POLYPRION. One dorsal ; anal two or three spines. 

 Operculum with strong bony ridge, and the bones toothed. 

 Many seas. 



Genus. OREOSOMA. Anal spines wanting. Scales none, 

 bony protuberances on body. Atlantic. 



Genus. APOGON. Lateral line commencing behind head. 

 Teeth on palatines. Praeoperculum with double serrated ridge. 

 First dorsal with six seven spines, anal with two, operculum 

 spined. Indian and Australian seas. 



Family. PRISTIPOMATID^E. Body compressed, scaled 

 teeth of scales sometimes wanting. Branchiostegals five, six, 

 or seven. Barbels none. Dorsal one ; no molar or cutting 

 teeth. 



Genus. PRISTIPOMA. Anal with three spines. Branchio- 

 stegals seven. Groove behind joint of lower jaw. Vertical 

 fins not scaly, or only at base. Indian and Australian seas. 



Genus. H^MULON. Soft parts of vertical fins scaly. Seas 

 of Tropical America. 



Genus. DIAGRAMMA. Branchiostegals six seven. Pores 

 in lower jaw, no groove ; upper profile of head rounded. Indian 

 seas. 



Family. MULLID./E Body long, slightly compressed ; 

 scales large. Two long barbels from under jaw. Branchio- 

 stegals four. Dorsal fins two, separate ; ventrals with one 

 spine and five rays. 



Genus. MULLUS. No teeth hi upper jaw. Many seas. 



Genus. UPENEUS. No teeth in palate, those of jaw in a 

 single series. 



Family. SPARIDjE. Body as last family ; tail not armed . 

 lateral line continuous. Branchiostegals five, six, or seven; 

 Teeth, either cutting in front of jaws or lateral series of molars. 

 One dorsal, anal three-spined ; ventrals under thorax, with one 

 spine and five rays. 



Genus. PAGRUS. Teeth conical in front, double series of 

 upper molars. Canines. Most seas. 



Genus. PAGELLUS. No canines ; rest as Pagrus. Most 

 seas. 



Genus. CHRYSOPHRYS. Three or more series of upper 

 molars. Canines. Mediterranean. 



Family. SQUAMIPENNES. Body much compressed 

 and deep, scaled. Lateral line continuous. Branchiostegals 

 six seven. Teeth in broad or narrow bands, sometimes teeth 

 on palate. Dorsal three or four, spined ; vertical fins covered 

 with small scales. Lower rays of pectorals branched ; ventrals 

 under thorax, with one spine and five soft rays. All tropical 

 species. 



Sub-family. CH.STODONTIN.*. No teeth on palate or 

 vomer. 



Genus. CH.UTODON. No praeopercular spine. Dorsal not 

 notched. Muzzle short. 



Genus. CHELMO. Muzzle very long. 



Genus. HENIOCHUS. Fourth dorsal spine very long. 



Genus. HOLOCANTHUS. Prasoperculum with strong spine, 

 dorsal with twelve to fifteen spines. 



Sub-family. TOXOTINA. Teeth on palate. Dorsal fin on 

 latter half of back. 



Genus. TOXOTES. Dorsal with five spines. 



Family. CIRRHITID^E. Body with cycloid (i.e. circular) 

 scales ; lateral line continuous. Branchiostegals three, five, 

 or six. Anal fin three-spined. Lower rays of pectorals simple. 

 Ventrals under thorax, one spine and five rays. Tropical and 

 warm seas. 



Genus. CIRRHITBS. No teeth on palate : dorsal spines 

 ten; intermaxillary bone not notched. 



Family. TRIGLID^E. Cleft of mouth extending to sides 

 of muzzle, and partly vertical; eyes directed upward. Pras- 

 operculum jointed to the sub-orbital ring. Two dorsals. Ven- 

 trals under thorax. Branchiostegals five to seven. Most seas, 

 especially the Northern. 



Group I. Body scaled or naked. 



Section I. Spinous dorsal developed as much as or more 

 than the soft and anal. 



Sub-family, SCORP.SNINA. Anal fin short. 



