210 ACANTHOPTERYGII. 



Family, XVI— CAKANGID^, Gunther. 



Scomberoidei, pt., et Squa/nwpwmes, pt., Cuv. : Scombrisidce, pt., Richardson. 



Branchiostegals usually seven, occasionally less : pseudobranchias as a rule present, but absent in 

 LicMa and Trachynotus. Body oblong, elevated, or sub-cylindrical and compressed. Gill-openings wide. 

 Eyes lateral. Infraorbital bones do not articulate with the preopercle. Dentition varied. The length of the 

 base of the spinous portion of the dorsal fin is of less extent than that of the soft, and is sometimes formed 

 by isolated spines : the spinous may be continuous with or distinct from the soft portion : the posterior 

 portion both of the dorsal and anal sometimes consists of detached finlets : the soft dorsal and the anal of 

 nearly equal extent. Anal spines, when present, may or may not be continuous with the soft portion. 

 Ventrals, when present, thoracic, sometimes rudimentary. Scales usually small, unless absent. Lateral-line 

 may be wholly, partially, or not at all armed with shield-like plates. Air-vessel present. Pyloric appendages 

 usually in large numbers. Vertebra 10/14 (Naucrates 10/16). 



SYNOPSIS OP GENERA. 



1. Garanx. Lateral-line wholly or only partially formed of plate-like scales, each of which is armed with 

 a lateral spinate keel. 



2. Micropteryx. Lateral-line smooth : abdomen trenchant. 



3. Seriola. Lateral-line smooth : abdomen rounded. 



4. Seriolichthys. Lateral-line smooth : a finlet behind the dorsal and anal fins. 



5. Naucrates. Lateral-line smooth : dorsal fin reduced to a few spines : no finlets : pre-anal spines in 

 the yonng. A keel on either side of the tail. 



6. Oliorinemus. First dorsal formed of isolated spines : posterior rays of dorsal and anal fins in the form 

 of finlets : dermal productions usually lanceolate. 



7. Trachynotus. First dorsal formed of isolated spines : no finlets behind dorsal and anal fins. Scales 

 rounded. 



8. Psettus. No pre-anal spines : ventrals rudimentary : no finlets : vertical fins scaled. 



9. Platax. No pre-anal spines : ventrals well developed : no finlets : vertical fins scaled. 



10. Psenes. No pre-anal spines : two separate dorsal fins : no finlets behind dorsal or anal fins. 



11. Equula. No pre-anal spines. Mouth very protractile. Teeth small and of equal size. Scales 

 cycloid. 



12. Gazza. No pre-anal spines. Mouth very protractile. Canine-like teeth in the jaws. Lower edge 

 of preopercle serrated. 



13. Lactarius. No pre-anal spines. One or two pairs of canines. Lower edge of preopercle entire. 



Genus, 1 — Caranx, Lacep. 

 Trachurus, Olistus, Blepharis, Gallichthys, Scyris, et Hynnis, Cuv. and Val. :* Megalaspis, Decapterus, Selar, 

 Carangichthys, Garangoides, Leioglossus, Uraspis, Selaroides, Gnathanodon, and Memicaranx, Bleeker : Garangus 

 (C. and V.) Girard : Trachurops, Carangops, and Paratr actus, Gill. 



Branchiostegals seven : pseudobranchice. Body oblong, sub-cylindrical, and more or less compressed. Eyes 

 lateral. Dentition feeble. Two dorsal fins : the first continuous, having about eight weak spines, ivhich are sometimes 

 rudimentary, at its base anteriorly is a recumbent spine directed forwards : the second dorsal longer than the first and 

 similar to the anal : sometimes the last rays of both these fins wholly or only semi-detached : two pre-anal spines 

 (which may be rudimentary) they are separated by an interspace from the rays. Scales minute. Lateral-line ivith 

 an anterior curved portion, ivhilst the posterior is straight, having large plate-like scales, winch are usually keeled and 

 sometimes spinate. Air-vessel bifurcated posteriorly . Pyloric appendages in large numbers. 



* The following arc the principal distinctions of the genera instituted by Cuv. and Val., which are inclnded in Genus Caranx 

 of Lacepede. 



1. Trachwrus. Lateral-line entirely covered by plate-like, keeled scales. 



2. Caranx. Subdivided into (1) those with several finlets : (2) a single finlet : (3) no finlets, form but little elevated and profile 

 nearly straight: (4) those having the skull elevated and compressed, and the dorsal profile forming the arc of a circle, or the Carangues : 

 (5) the last group with the points of the dorsal and anal very prolonged, or Citulas. 



3. Olistus are Citulas with several of their dorsal and anal rays being unbranched and having filamentous terminations. 



4. Blepharis. Body as high as long, and a very elevated profile. A rudimentary first dorsal fin. A portion of the anterior 

 dorsal and anal rays filamentous. 



5. GalUcMhys. Body less elevated. A rudimentary first dorsal fin. Anterior dorsal and anal rays prolonged into filaments. 

 Ventrals very long. 



6. Scyris. Profile more like the last, with short ventrals. 



7. Hynnis. No first dorsal fin. No filamentous prolongation of the rays. Ventrals short. 



