SCOMBEIIOIDS. 121 



small but acate teeth ; these are sometimes present on the jaws only, 

 as in Atherina Brasiliensis and other species of the new world ; some- 

 times also they are developed, but of extremely minute size, upon the 

 palatine bones, as in the Atherina Hepsetus ; and lastly they may be 

 found on the jaws, palatines and vomer, as in the Atherina Boieri, and 

 other broad and fiat-headed species of the present family. The 

 pharyngeal bones in the common Atherine or sand-smelt, fAtherina 

 PresbyterJ, are furnished with numerous small and close-set conical 

 teeth. 



SCOMBEROIDS.(l) 



51 . In this family of cycloid fishes the dental system presents many 

 modifications, of which the Sword-fishes fXiphiasJ, and the Scabbard- 

 fishes (LepidopusJ offer, perhaps, the extremes. 



The Sword-fish might be reckoned among the edentulous fishes, 

 were it not that the pharyngeal bones are covered with a villosity 

 of extremely fine and minute denticles ; but all the ordinary bones 

 of the mouth, of the tongue, and even of the branchial arches, are 

 without teeth. In the Opali or King-fish, fLampris guttatusj, the 

 ordinary bones of the mouth are likewise edentulous ; the pharyngeals 

 have not been examined in this species. 



In the Stromateus there is a single row of denticles on each 

 jaw, but these are so delicate and short that they cannot be recog- 

 nised without the aid of a lens. The palatine, vomer, and hyoid 

 bones are edentulous, as in the Sword-fish. 



The dentition of the Rhombus is similar to that of the Stromateiis, 

 but the maxillary teeth are a little more developed. 



The margins of the jaws are roughened by numerous close-set, 

 short, villiform teeth in the Tetrapturus ; the palatine and pharyngeal 

 bones bear similar denticles in this genus. 



In the Histiophorus the broad, dentigerous margins of the jaws 

 are covered with minute dental granulations only, some of which are 

 developed, in the lower jaw, into small pointed teeth. 



The dental system is not more formidable in the genus Trachurus. 

 In the mailed mackerels, {Caranx), the tongue is beset with villiform 



(1) PL 53, b'i, and 55. 



