PERCESOCES 231 



of keeled scales along each side of the belly ; maxillae entering 

 border of upper jaw ; lower pharyngeals united into a single 

 bone ; no adipose fin ; pelvics without spines, with 6 rays ; air- 

 bladder generally present without duct ; pseudobranch hidden glandu- 

 lar ; stomach not distinct from intestine, which is quite straight, without 

 appendages. Chiefly marine, but some acclimatised in f . w. ; many 

 of the latter are viviparous. All trop. and temp, zones (Holosteus in 

 the strata of Monte Bolca is allied here). Belone Cuv., with 

 green bones, both jaws elongated into a beak, no finlets ; B. vulgaris 

 Flem., Brit, coast, gar-fish, gar-pipe, sword-fish. Scombresox Lac., the 

 saury or skipper, both jaws elongated into a beak, finlets behind 

 anal and dorsal fins ; S. saurus Rond., Brit, coast. Tylosurus, Ath- 

 lennes, Hemirhamphus, Arrhamphiis, Chriodorus, Hyporhamphus ; Exo- 

 coetus Art., flying fish (Fig. 127), both jaws short, pectoral fins elongated 

 into organs for floating through the air (parachute-like), they live in shoals 

 in trop. and sub-trop. seas, E. volitans L., has been taken off Brit, coast ; 

 flying fish do not fly, but leaving the water by a powerful tail movement 

 they float rapidly through the air in a straight line supported by their 

 expanded pectoral fins. Fodiator, Parexocoetus, Halocypselus. 



Fam. 50. Ammodytidae. Sand-eels. Small carnivorous fishes swim- 

 ming in shoals near the shore and burying themselves in the sand ; pelvics 

 absent ; vent remote from head, long dorsal and anal fins destitute 

 of spines ; pelvics without spine, with 6 rays ; no air-bladder. Ammo- 

 dytes L., A. lanceolatus, greater sand-eel ; A. tobianus, lesser sand-eel. 



Fam. 51. Atherinidae. Lateral line indistinct, with a silvery band 

 along the sides ; valued as food ; the fossil Mesogaster allied here. Ather- 

 ina L., littoral fishes living in shoals, like smelts ; the newly hatched 

 young are called nonnat in S. France. A. presbyter Jenyns, silverside, 

 and A. boyeri are British ; Lethostole J. and E. ; Chirostoma Swains. 

 (Atherinichthys Bleek), pesce rey ; Kirtlandia ; Menidia ; Leuresthes ; 

 Eur y stole ; Thyrina ; Atherinella ; Labidesthes ; Atherinopsis ; Atherinops. 



Fam. 52. Mugilidae. Grey mullets. Lateral line absent ; large cycloid 

 scales ; anterior dorsal of 4 stiff spines. Mugil L., grey mullets, stomach 

 muscular in part, like gizzard of fowl, feed on mud and sand, and have 

 long gill-rakers, along shores and in brackish lagoons, intestine much 

 convoluted and long, M. capita Cuv. grey mullet, and M. chelo Cuv. 

 lesser grey mullet, are British ; Chaenomugil, Querimana, Agonostomus, 

 Joturus. 



Fam. 53. Sphyraenidae. Barracudas. Lateral line continuous, small 

 cycloid scales ; carnivorous pike-like fishes, often of large size, inhabiting 

 warm seas, many used as food ; Sphyraena Bl. and Schn. 



Fam. 54. Polynemidae with Polynemus, Pentanemus, Galeoides, Poly- 

 dactylus ; flesh esteemed, air-bladder yields isinglass, humeral arch with 

 long filaments, sandy shores of trop. seas sometimes entering rivers. 



Fam. 55. Chiasmodontidae. Deep-sea ; Chiasmodon Johnson or 

 Chiasmodus Gthr., Pseudoscopelus Lutken. 



Fam. 56. Stromateidae, Pelagic or deep-sea fishes, with Nomeus, 

 Cubiceps, Psenes, Seriolella, Psenopsis, Centrolophus, Lirus, Stromateus, 

 Peprillus, Stromateoides. 



Fam. 57. Tetragonuridae. Tetragonuriis, a rare fish from Mediter- 

 ranean, Atlantic and S. Pacific, poisonous as food. 



Fam. 57a. Icosteidae. Icichthys, Icosteus, Acrotus, all deep-sea. 



Fam. 58. Ophioeephalidae. Fresh-water fishes of the Indian region 



