196 FlSilES. 



Chalceus, Cuv., 



Have the same form of mouth, and the same trenchant and notched teeth 

 as in the preceding subgenus, but the body is oblong and neither carinated 

 nor dentated; very small, round teeth in the maxillaries*. 



Myletes, Cuv. 



These fishes are remarkable for their very singular teeth, which re- 

 semble short triangular prisms, rounded on the ridge, and excavated on 

 the superior surface of the crown by mastication, so that three salient 

 points are formed there by the three angles. There are two ranges of 

 these teeth in the intermaxillaries of the slightly cleft mouth, and a single 

 one in the lower jaw, with two teeth behind; the palate and tongue, how- 

 ever, are smooth. The maxillaries placed on the commissure have no 

 teeth. 



Some of them have the elevated figure, the falciform vertical fins, for- 

 wardly inclined spine, and even the trenchant and notched abdomen of 

 the Serra-salmi, to which, but for their teeth, we should certainly unite 

 them. One of them even has a horizontal spine in front of the dorsal -i-. 

 Very large ones, whose flesh is much esteemed, are found in America |. 



Others have an elongated form, the first dorsal being opposite to the 

 interval between the ventrals and the anal. The species known are only 

 found in Egypt §. 



Hydrocyon, Cuv., 



Have the end of the snout formed by the intermaxillaries; tlie maxillaries 

 commencing near the eyes, or before them, and completing the upper jaw. 

 The tongue and vomer always smooth, but both jaws are furnished with 

 conical teeth ; a large suborbital, thin and naked like the operculum, 

 covers the cheek. 



Some of them have a compact range of small teeth in the maxillaries 

 and palatines, their first dorsal corresponding to the interval between the 

 ventrals and analj]. They inhabit rivers in the torrid zone; their flesh 

 resembles that of the Carp^. 



Others have a double row of teeth in their intermaxillaries and lower 

 jaw, and a single one in the maxillaries ; but their palatines have none. 

 Their first dorsal is above the ventrals**. 



* Chalceus macrolcpidotus, Cuv., Mem. Mus. IV, pi. xxi, f, 1; — Ch. opalinus, Id., 

 lb. V; pi. xxvi, f. I ;—Ch. angulatus, Spix, XXXIV. 



f Myletes rliomboidulis, Cuv., Aiem. du Mus. IV, pi. xxii, f. 3. 



X Add to the preceding species, Myl. durivetitrh, lb., f. 2; — M. hrachypomus, lb., 

 f. 1 ; — M. macropumiiti, lb., pi. xxi, f. 3; — M. pnco, Humb. Zool. Obs. II, pi. xlvii, f. 2. 



ij The Raii of the Nile, vvhicli is the Ci/prinus denies, L., Mus. Ad. Fred, and ed. 

 XII, or the Snlmo denta-, Hasselq., and the S. nlloticus, Forsk., and which is thus 

 twice found in Gmelin and his successors. It is the Myl. Husselquistii, Cuv., Mem. 

 Mus. IV, pi. xxi. f. 2. 



II It is for this reason that M. de La'.apede placed them among the Osmeri. 



^ Snlmnfulcatiis, Bl. .jS5; — /S. ot/oe, Id. SSfi; — Hijdiucyonfalc'tiostris,C\xv., Mem. 

 Mus. V, pi. xxvii, f. ] i — Hyd. hepsclus, Cuv., or Hydr. jaucille, Zool. Voy. de Frevcin., 

 pi. 48, f. 2 



** .\ new species from Brazil, the Ilydmc. b:eviJens, Cav., Mem. Mus. V, pi. xxvii, 

 f. 1, or Characiuus amazoiiinis, Spix, XXXV. 



