SYSTEMATIC CATALOGUE OF FISHES. 53 



p'. Dorsal fin with soft rays anteriorly and spines posteriorly; ventral fins very 

 small; gill-membranes broadly joined to isthmus; form elongate. 



ZoARCiD^ (eel-pouts). 

 pp'. Dorsal fin with spines anteriorly and soft rays posteriorly. 



g'. Cheeks covered with bony armor; pectoral fins divided, the lower part 

 very large hke the "wing" of a fiying-fish. 



Cephalacanthid^ (fljing-gumards). 

 qq'. Cheeks not covered with bony armor; pectoral fins not divided. 



r'. Dorsal fins 2, the spines 3; gills 3; mouth very large and fringed; size 



moderate Batrachoidid^ (toad-fishes). 



rr'. Dorsal fin single, the spines numerous (at least 11); gills 4; mouth 



small not fringed; size small Blenniid^ (blennies). 



oo'. Upper jaw produced in the form of a powerful sword; fishes of very large 



size IsTioPHORiDiE (sail-fishes). 



nn'. Dorsal fins without spines; a large sucking-disk between ventral fins. 



GoBiESOCiD^, in part (cling-fishes). 

 IV. Ventral fins absent. 



a. Body eel-shaped; maxillary and premaxillary bones absent or fused with palatines. 

 b. Gill-openings vertical, usually well developed; skin with or without scales; a tongue 

 present; pectoral fins present or absent, 

 c. Skin covered by rudimentary linear scales; pectoral fins well developed. 



Anguillid^e (common eels). 

 cc. Skin scaleless. 



d. Tip of tail with a distinct fui, confluent with the dorsal and anal; pectoral fins well 

 developed; dorsal fin beginning posterior to gill-openings; mouth large. 



Leptocephalid^ (conger eels). 



dd. Tip of tail without a fin and projecting beyond dorsal and anal fins; pectoral fins 



rudimentary (in local representative) ; dorsal fin beginning on head; mouth small. 



Ophichthyid^ (snake eels). 

 hb. Gill-openings small, roundish; skin scaleless; tongue absent; pectoral fins absent. 



MuR^NiD^ (morays). 

 aa. Body not eel-shaped; maxillary and premaxillary bones present, 

 e. GUI-membranes broadly joined to isthmus. 



/. Snout tubular, with a small, toothless mouth at end; body more or less encased in 



bony rings Syngn.\thid^ (pipe-fishes and sea-horses). 



//. Snout not tubular; body not encased in bony rings. 



g. Two dorsal fins, anterior with spinous rays, posterior with soft rays; body deep and 

 greatly compressed. 

 h. Dorsal spines 2 or 3 in number; skin covered with small, rough scales. 



Balistid^ (trigger-fishes). 

 hh. Dorsal spine single; skin covered with minute, rough scales, 



Monacanthid^ (file-fishes). 

 gg. One dorsal fin, composed of soft rays only. 

 i. Teeth in each jaw fused into 1. 



j. Body compressed; dorsal and anal fins very high and pointed; skin with- 

 out spines; size very large Molid^ (head-fishes). 



//. Body not compressed; dorsal and anal fins small; skin thickly covered with 



long spines; size moderate Diodontid^ (porcui^ine-fishes). 



a. TeetU in each jaw fused mto 2; skin more or less prickly. 



Tetraodontid^ (puffers). 

 iii. Teeth in each jaw not fused; body encased in a bony armor. 



OsTRACiiD.aE (trunk-fishes). 

 ee. Gill-membranes not joined to isthmus. 



k. Ventral opening at throat; body elongate; dorsal fin single, short, of soft rays only; 



size very small Amblyopsid.e (swamp and cave fishes). 



kk. Ventral opening situated posteriorly. 



I. Mouth large; body elongate, without scales; size large. 



m. Jaws nearly equal, and armed with large teeth; body very long, compressed; 

 dorsal fin low and extending entire length of body; caudal fin absent. 



Trichiurid^ (cutlass-fishes). 

 mm. Upper jaw produced to form a long, powerful sword; mouth toothless; body 

 moderately elongate, not compressed; caudal fin large and forked. 



XiPHiiD^ (sword-fishes). 



IL Mouth small; body compressed and deep, and covered with small scales; dorsal 



and anal fins elongate, with interior rays produced; caudal deeply forked; size 



small STEOMATEID.E (butter-fishes). 



