58 ORDERS, SUB-ORDERS, AND FAMILIES. 



SCOMBRESOCID^;. Body long and rounded. Dorsal rayed and opposite 

 anal. Scales keeled along free portion of tail. Lower pharyngeals 

 united into one bone. Pseudobranchiae glandular and hidden. 

 Belone, 87 ; Exocatus, 89, go ; Scombresox, 88. 



SCOMBRID.E. Body slightly compressed. Two dorsals, first with fewer 

 spines than second has rays, finlets behind dorsal and anal occasionally 

 absent; ventrals thoracic, with one spine and five rays Side of tail 

 sometimes keeled. Scales small or abssnt. Eye lateral. Infraorbitals 

 not articulated to praeoperculum. Gill opaning wide. Auxis, 43 ; 

 Echeneis, 44 ; Orcynus, 39, 40; Pelamys, 42; Scomber, 36 to 38 ; Thynnus, 41; 



. Body oblong, compressed, or sub-cylindrical. Dorsal with 

 spinous part as large or larger than the soft part ; soft part similar to 

 anal ; ventrals thoracic, generally with a spine and five rays, but 

 sometimes rudimentary. Some of the head bones armed ; armature of 

 angle of praeoperculum supported by the stay to the infraorbital ring. 

 Teeth in villiform bands. Pseudobranchiae present. Branchiostegals, 

 five to seven. Sebastes, 19, 



Body oblong, compressed. One dorsal, spinous and soft por- 

 tions equally developed; anal with three spines; ventrals thoracic, of 

 one spine and five rays. Lateral line not extending to caudal. Scales 

 cycloid or minutely ctenoid. Eye lateral. Mouth lateral, in front of 

 snout ; cutting teeth in front of jaws, or a lateral series of molars, or 

 both. Pseudobranchiae well developed. Branchiostegals, five to 

 seven. Box, n ; Cantharus, 10 ; Pagellus. 1410 18 ; Pagrus, 12, 13. 



. Body oblong and compressed. One dorsal, long and 

 without distinct spinous division, or with rudimentary spines in front ; 

 ventrals thoracic. Scales very small. Eye lateral. Teeth very small 

 in jaws, palate toothless, oesophagus with barbed teeth. Praeoper- 

 culum not articulated with infraorbitals. Gill opening wide. Centro- 

 lophus, 30, 31. 



TRACHINID^E. Body long, hinder part compressed ; head often large 

 One or two dorsals, spinous portion shorter and less developed than 

 the other ; anal similar to soft dorsal ; pectorals with or without 

 appendages ; ventrals thoracic, with one spine and five rays. Scales 

 present or absent. Teeth small and conical. Praeoperculum not 

 articulated with infraorbitals. Tra hinus, 45, 46. 



TRACHYPTERID^. Body riband-shaped; bones porous, thin, and light. 

 Dorsal as long as back, rays unbranched and not articulated, front 

 portion detached ; anal absent ; caudal at an angle to the longitudinal 

 axis or rudimsntary ; ventrals jugular and filamentary. Scales absent. 

 Eye lateral. Mouth cleft small. Teeth small and smooth. Gills 

 four ; gill opsning wide. Pseudobranchiae present. Regalecus, 103 ; 

 T r achy p terns, 102. 



TRICHIURID^. Body long, compressed or riband-shaped. Dorsal and 

 anal long and many rayed, and nearly similar in size, and occasionally 

 ending in finlets ; caudal forked or absent ; ventrals thoracic, some- 

 times rudimentary. Scales absent or rudimentary. Eye lateral. 

 Mouth cleft deep. Teeth in jaws or on palate, a few of them strong 

 and conical. Gill opening wide. Lepidopus, 23 ; Trichiunis, 22. 



