EL0P8. THE SUB-GENERA. 283 



the elongated lower jaw of Flops saurus opens a pas- 

 sage to the sub-genus Megalops: in this we still have 

 the rounded belly of the last fishes; but from them, and 

 all others of the toothed herrings, they may at once be 

 distinguished, on account of their possessing a dorsal fin 

 shaped exactly like that of Chatoessus — that is, with the 

 last ray prolonged into a filament : all the species have 

 conspicuous teeth, close and even upon their jaws ; and 

 some also have them on the palatines : the gill mem- 

 branes, as mElops, has a great number of rays, but these 

 vary among the species ; while in some the last ray of 

 the anal corresponds to that of the dorsal, in being also 

 prolonged into a filament : this deviation is particularly 

 seen in an immense species found in America, which 

 sometimes grows to the length of twelve feet. Other 

 species occur in the Atlantic; and Dr. Russell has 

 figured some from India. The next type in our series 

 is that of Notopterus Lac, founded upon a rare In- 

 dian freshwater fish, considered by Pallas as a Gym- 

 notus*, but removed by Cuvier to this family. Never 

 having seen a specimen, we must take for granted that 

 the great ichthyologist of France is correct in this view 

 of its affinities ; and, judging from the figures that have 

 been published, we join in the same opinion. The 

 general aspect of this fish is that of a herring ; but it 

 differs from the three preceding types of this division 

 by having the carinated edge of the belly serrated, the 

 ventrals remarkably small, and the anal long, narrow, 

 and united to the caudal fin : this latter character we 

 have not hitherto noticed in the whole of this family, 

 and for subsequent reasons it deserves great attention : 

 not only the jaws, but the palatines and the tongue, are 

 all armed with teeth ; those on the two former are fine, 

 but those upon the tongue are strong and hooked. In 

 most of the toothed herrings, the number of the branchial 

 rays are remarkably numerous; but in this, according to 

 Cuvier, there is but one, which is strong and osseous. 

 We have now enumerated four of the types, and we 



* Pallas, Spec. Zool. vol. vi. pi. vi. fig. 2. Bontius, Ind. p. 78. 



