BONY FISHES AND GANOIDS. 479 



eight feet in length, and weigh forty pounds, are all included in the one 

 genus Sphyrwna. As a family, they are characterised by the long and some- 

 what eel-like form of the body, the small cycloid scales, continuous lateral 

 line, the wide cleft of the mouth, which is armed with formidable teeth, and 

 the moderate-sized and laterally-situated eyes. They are fierce and voracious 

 fishes, inhabiting tropical and sub-tropical coasts. Although extensively 

 used as food, their flesh is at times apt to develop poisonous properties. 



Passing by the small family of the Atherinidce, of which the most familiar 

 representatives are the so-called sand-smelts (Atherina) of the Mediterranean, 

 with the bare mention that the lateral line is feebly and in- 

 distinctly developed, we come to the more important group Family 

 of the grey mullets, most of which are included in the genus Mugilidm. 

 Mugil, and all of which lack the structure last mentioned. 

 They have the same number (24) of joints in the backbone as the Sphyrcenidw, 

 whereas in the Atherinidce, these are considerably more numerous. Grey 

 mullets have a narrow cleft to the 

 mouth, none or feeble teeth, and a 

 very sharp, but rather tall first dorsal 

 fin, which is composed of four stiff' 

 spines only. The members of the 

 genus are numerous, and common on 

 temperate and tropical coasts, where, 

 according to Dr. GiLnther, "they 

 frequent brackish waters, in which 

 they find an abundance of food, which j,^^ 13.-Gkey Mullet. 

 consists chiefly of the organic sub- 

 stances mixed with mud or sand. In order to prevent larger bodies from pass- 

 ing into the stomach, or substances from passing through the gill-openings, these 

 fishes have the organs of the pharynx modified into a filtering apparatus. 

 They take in a quantity of sand or mud, and, after having worked it for 

 some time between the pharyngeal bones, they reject the roughest and in- 

 digestible portion." Most of the species grow to about four pounds weight, 

 although some reach as much as ten. 



The garpike {Belone), the sauries {Scomhresox), and the flying-fish {Exoccetus), 

 collectively constitute a section and family characterised by the feeble 

 development of the spines of the fins. They have the pelvic 

 fins abdominal in situation, and are especially distinguished Section Scom- 

 by the union of the pharyngeal bones, the absence of a spiny bresociformes. — 

 dorsal fin, and the forked tail-tin ; the rayed dorsal being Family Scombre- 

 placed in the caudal region immediately over the anal. Al- socidm. 



though false gills are present, these are concealed and 

 glandular. As a rule, the air-bladder is retained. A peculiar feature of the 

 family is the simple structure of the stomach, which forms a mere expansion 

 of the intestinal tract. Members of the family are to be met with in all 

 temperate and tropical seas, some of them, like the flying-fish, being truly 

 pelagic in their habits. Fresh-water forms, although few, are, however, by 

 no means wanting ; and it is somewhat remarkable that most of these— un- 

 like their marine relatives— give birth to living young, instead of depositing 

 spawn. The garpike, of which one species is commonly met with in the 

 British seas, are specially characterised by the elongation of the jaws to form 

 a long tubular beak, and the connection of all the rays of the anal and dorsal 

 fins (which are precisely similar) by membrane. Young garpike are, how- 



