W. S. MacLeay on the Natural Arrangement of Fishes. 201 



By means of Polynenws we pass from Scicena to the Cirrhitidce, 

 which differ from the Percidts in having in general either more or 

 less than seven branchial rays, and from the Sparidcn in having teeth 

 generally on the palatines. The Clrrhitidce, however, differ from each 

 other very much in form, as may be seen by the following genera, 

 which are clearly of the rank of families :• — 



Two dorsals. 



1. PoLYNEMus, Linn. Two dorsals distinct. Ventrals sub- 



abdominal. 



2. MuLLus, Linn. Two dorsals distinct. Ventrals sub- 



pectoral. Brancliial rays less than 

 seven. 



3. Traciiinus, Linn. Two dorsals luiited. Ventrals sub- 



jugular. Branchial rays more than 

 seven. 

 One dorsal, ventral fins subpectoral. 



4. Beryx, Ciiv. Branchial rays more than seven. 



5. CiRRHiTEs, Conem. Branchial rays less than seven. 



By means of Trachiims we return among the Scorpcenidat, from 

 Avhich we set out, so that the circle of PERCINA is completed. We 

 now therefore proceed to the next tribe, FISTULARINA, which we 

 enter by reason of the affinity reigning between the Chcetodontidai and 

 Scombridce, as displayed in such genera as, for instance, Brama and 

 CorypluEuu . 



Probable genera of the Scombridce, or family Scomberoides of 

 Cuvier. 



Body regular and pisciform. 



1. CoRYPHyENA, lyilin. 



2. XiPHiAs, Linn. 



3. Scomber, LAnn. Leading off by Thyrsites to Lepidopns. 



Body laterally compressed and vertically elevated. 



4. Stromateus, Linn. Ventrals inconspicuous. 



5. Zeus, Linn. Ventrals conspicuous. 



By Lepidopus we enter among the FistularidcB, or long eel- shaped 

 Acanthopterygians, which may be arranged as follows : — • 

 TjENOIDES, Cm: One long dovsal. Cranium not produced into a tube. 

 Body tolerably compressed. 



1. Lepidopus, Go«aH. Muzzle elongated; month consider- 



ably cleft, and a caudal fin present. 



2. Cepola, Linn. Mouth considerably cleft; nocaudalfiu. 



3. Gymnetiius, Bl. Muzzle elongated, mouth small, cau- 



dal fin present. 

 FISTULARIDES, Cnv. Cranium produced into a tube. 



4. Centriscus, Lirm. Body oval, compressed ; scales con- 



spicuous ; dorsals two. 



5. FisTULARiA, Litin. Body elongated, cylindrical ; scales 



small ; only one dorsal. 



By Aalosf omits we return to Lepidopus, and by means of Gymiietrus 

 and one of its subgenera, Murcenoidcs, we pass to the Gobioidec, a 

 family easily known by the extreme length and tenacity of their dorsal 



Ann. i^' Mag. N. Hist. Vol.ix. P 



