PISCES. 



663 



brought togetner, ana triDes that are really allied being widely separated. The following classification, whicn is 

 that of Protessor Miiller, slightly modified by Professor Owen, being founded on the general orgavixaticn of the 

 animals it includes, has more title to be considered a natural one, and represents the nearest approach to a perfect 

 arrangement which the present state of knowledge admits. 



Oedeb I.— DERMOPTERI. 



Internal skeleton unossified ; integument and vertical fins muco-derraoid ; vermiform, or abrachial and apodal ; 

 no pancreas, no air bladder. 

 Sub-order 1. Phaetngobranchii, (or Cirrhostomi.) Gills free, pharyngeal, inoperculate; no heart. 



Family. — ArnpMoxidce. Example. — Lancelet. 

 Sub-order 2. MARSirOBRANCHii, (or Cyclostomi.) Gills fixed, bursiform, inopereulate, receiving the respiratory 

 streams by apertures usually numerous and lateral, distinct from the mouth ; a heart. 



Family.— Myxinoidci. Example.— My ^ine or Hag, Family.— PetromyzontidcE. Example.— Lamprey. 



Order II.— MALACOPTERI. 



Internal skeleton ossified ; external skeleton in most as cycloid, in a few as ganoid, scales ; fins supported by 

 rays, all, save the first sometimes in the dorsal and pectoral, soft or jointed; abdominal or apodal ; gills free, 

 operculate ; a swim-bladder and air duct. 

 Sub-order 1. Apodes. 



Family.— Symbranckidw. Example.— Cachia. Family. — Mttrcenid a; . Example.— 'Eil. 



Family. — GymnotidcE. Example. — Gymnotus. 



Sub-order 2. Abdominales. 

 Family.— JTeteropygii. Example. — .\mbly0psi3. 

 Clupeidee. Herring. 



SalmonidcE. Salmon. 



ScopelidoB. Saurus. 



Charadni. Myletes. 



Family. — Eilurid^e 



iFamVy. — Galaxida;. 

 Esocidce 

 Mormyridce 

 Cyprinodoritidce 

 CyprinidcB 

 Example — Sheat Fish. 



Example, — Galaxias. 

 Pike. 



Mormyrus. 

 Umber. 

 Carp. 



Order III.— PHARTNGOGNATHI. 



Internal skeleton bony; external skeleton in some as cycloid, in others as ctenoid, scales; inferior pharyngeal 

 bones coalesced ; swim-bladder without duct. 

 Sub-order 1. Malacoptertgii. 



Family. — Seomber-esocidce. Example. — Saury-pike. 

 Sub-order 2. Acanthopterygii. 



Family.— Chromidcc. Example.— Chromis. Family.— Cyelo-Labridce. Example —Wrasse. 



Family.— Cteno-Lahridijc. Example. — Pomacentrus. 



Order IV.— ANACANTHIXI. 



Internal skeleton ossified ; external skeleton in some as cycloid, in others as ctenoid, scales ; fins supported by 

 flexible or jointed rays ; ventrals beneath the pectorals, or none; swim-bladder without air duct. 

 Sub-order 1. Apodes. 



Family. — OpTiididm Example. — Ophidium. 

 Sub-order 2. Thoracici. 



Family. — Oadida:. Example. — Cod Family. — Plettroncetida- . Example. — Plaice. 



Order V.-ACANTHOPTERI. 



Internal skeleton ossified ; external skeleton as ctenoid scales ; fins with one or more of the first rays unjointed 



or inflexible spines ; ventrals in most beneath, or in advance of the pectorals; swim bladder vrithout duct. 



Family. Example. 



Squamipennes. Chsetodon. 



Tcenioidei. Riband-fish. 



TheutyidoB. Lancet-fish. 



Fistvlarida;. Pipe-mouth-fish. 



OobiidcB. Goby, Remora, and Lump-fish. 



BlenniidcE. Blenny and Wolf-fish. 



Lophiidce. Angler. 



Order VI.— PLECTOGNATHI. 



Internal skeleton partially ossified ; external skeleton as ganoid scales or spines ; maxillarics and pre-mnxill.i- 

 ries fixed together; swim-bladder without air ducts. 



Family. — Balistinm. Example.— Y\le-fish. FamUy. — Ostraciones. Example — Trunk-fish. 

 Family. ^Gymnod<nxtes. Ecampf?, —^Glohe-fish. 



