BONY FISHES AND GANOIDS. 503 



gentleman's servant who had been drowned. The pike has often been caught 

 with portions of tackle broken frc^m the line in former engagements hanging 

 from its mouth. Its rapacity is extraordinary. Eight hundred gudgeon are 

 said to have been consumed in three weeks by eight pike of not more than 

 five pounds weight each." 



Section E. — Scyphophori. 



The next family of the Physostomi comprises a few fishes from Tropical 

 Africa which appear to have no very near relations, and are consequently re- 

 garded as forming a sectional group by themselves. The 

 chief characters of the section are derived from the bones of Family 



the skull, in which the parietals are separate alike from one Mormyridce. 

 another, and from the supraoccipital ; while the pterotic 

 bones, which are situated on the outer sides of the parietals, are large, funnel- 

 shaped, and contain a cavity closed by a lid. The full series of bones are 

 developed in the gill-cover, and in the back-bone the four first joints are 

 separate and unmodified. As a family, the Mormyridce are characterised by 

 the naked head, the want of barbels, the slit-like opening of the gills, the 

 simple air-bladder, and the absence of a fatty fin on the back. The front 

 portion of the margin of the upper jaw is constituted' by the premaxilte, 

 which are united together ; but the sides are formed by the maxillse. All 

 these fishes are dwellers in fresh water. The typical genus is Mormyrus, 

 from which some writers distinguish certain species under the name of 

 Mormyrops, other members of the family being included in Gymimrchus, 

 which is characterised by the complete disappearance of the pelvic, anal, and 

 caudal fins, the tail terminating in a point. Many of the species of Mormyrus 

 have the muzzle more or less elongated and beak-like, but M. petersi has the 

 extremity of the lower jaw produced into a large, conical, fleshy appendage 

 of great relative length. Gynmarchus — of which there is only one species — is, 

 on the other hand, a large eel-like fish, growing to a length of a couple of 

 yards. 



Section F. — Isospondyli. 



The sixth and last section of the Physostomi is the largest and most im- 

 portant of all, including — in addition to many other groups — the families of 

 the herrings and salmon, whose numerous representatives are so highly 

 valued as food. 



These fishes are the most generalised of all the Physostomi, and conse- 

 quently make the nearest approach to the under-mentioned ganoids. In all 

 of them the two parietal bones are separate, and the so-called 

 sympleotic bone, which is wanting in the preceding family, is Family 



here present. As in the latter, the anterior segments of the Nolopteridie. 

 vertebral column are of the simple, unmodified type ; but 

 both the upper and the lower pharyngeal bones are separate. The first 

 representative of the section is the genus Notopterus, which constitutes a 

 family by itself, and includes several species from the Oriental countries and 

 West Africa. None of these fishes have a fatty dorsal fin or barbels, but 

 many of them possess a short ftnd t£^ll dorsal fin, situated far back on the body, 



