ICHTHYOLOGY. 



273 



Classifica- g'li- Anus generally before the. middle of the'fish, and the tail often 

 tjon— considerably longer than the body. One or two dorsals ; edges of the 

 Acanthop- preorbitar and preopercular pieces entire ; not serrated ; sometimes 

 terous a strong spine from the surface of the operculum, or from the 

 Fishes, shoulder. Mouth formed above entirely by the premaxiUaries, 

 V. ^ .^ y with the raaxiilaries in the membrane behind them; teeth on the 

 ' jaws and vomer ; palatine teeth in some present, in others none. 



Jiranchiostegals six or seven, rarely five. Abdominal cavity some- 

 times prolonged past the anus; no air-bladder; caical stomach; 

 pancreatic ceeca three to twelve, or more, sometimes none (Hemero- 

 coetus). 



Genus I. Trachinus, Linn. Head compressed ; a strong oper- 

 cular spine. Villiforra teeth on the jaws, on the anterior point of the 

 vomer, on the fore end of the palatines, on the entopterygoid, on the 

 pharyngeals, and on the short tubercles of the branchial arches. 

 Cranium more or less rough, and the suprascapular finely denti- 

 culated. A small spinous dorsal far forward, and not connected 

 to the soft dorsal. Abdominal cavity of small extent. Four 

 species. 



Genus IL Percis, Bloch. Trackini, with the head more de- 

 pressed and the spinous and soft dorsal joined ; vomerine, but no 

 palatine teeth ; somewhat of a Labroid aspect. Some were described 

 as Lahri by Schneider, and Bloch named another EnchehjopuSy con- 

 ceiving it to be a Gadoid fish. Cavity of the abdomen not exten- 

 sive. Fifteen species. 



Genus IIL Pinguipes, Cuv, The Labroid aspect of this 

 genus is striking. Lips thick, covering the strong, conical, and 

 somewhat curved teeth. A single dorsal spinous in front, without 

 a notch between. Vomerine and palatine teeth. Three species. 



Genus IV. Uranoscopus, Linn. Head large, cubical, bony, 

 rough, and sculptured, depressed with the protractile eyes on the 

 dorsal aspect. Mouth cleft vertically, so that the mandible forms 

 the extremity when it is closed against the abbreviated snout. Sub- 

 orbitars large, cuirassing the cheeks, but attached to the temples, and 

 not forming a fulcrum to the spinous preoperculum as in the Sclero- 

 genidm. Scales small, cycloid. Nominally two dorsals, but some 

 species want the spinous one. A humeral spine, which in some is 

 large and crenated. £;ome have a barbel at the symphysis of the 

 mandible externally, and some have a filament under the tongue 

 within the mouth. Branchiostegals six. Stomach caecal ; pancrea- 

 tic Cceca numerous (twelve). Seventeen species. 



Genus V. Bovichthys. External aspect of Co«tt«. Head large, 

 depressed, rounded, with large eyes near the dorsal plane. Mouth 

 terminal ; villiform teeth on the jaws, vomer, and palatines, the 

 outer row on the jaws being thicker and taller. No scales. Skin 

 very porous, mucoducts disposed in branching lines on the head, 

 and strongly prominent along the lateral line. Branchiostegals 

 seven. Fins large, the two dorsals contiguous; five lower pectoral 

 rays, and all the anal rays, except the two posterior ones, simple 

 and projecting beyond the notched membrane ; the pectoral re- 

 sembling that fin in Coitus, and the anal that of Trachinus. Oper- 

 culum ending in a large flat spinous point, clothed with skin ; no 

 other particular armature of the head ; a curved spine from the front 

 of the operculum being quite hidden by the soft parts. 



Genus VI. Percophis, Cuv. A long slender fish resembling 

 Spktfrcena. Head pointed ; mandible prominent ; teeth strong, 

 curved ones in front of villiform bands in the jaws ; teeth also on 

 the vomer and palatines. Anus at the end of the anterior third of 

 the whole length. First dorsal posterior to the base of the pectorals 

 at a little distance from the long soft dorsal ; anal longer than the 

 latter. A small opercular spine. Branchiostegals seven. Scales cili- 

 ated. Abdominal cavity prolonged to a considerable distance be- 

 yond the anus; stomach caical. One species. 



Gexos VII. Hemeroccetes, Cuv. Form elongated, slender, 

 roundish, tapering but slightly towards the tail, with a long even 

 dorsal and anal separated from the caudal. Dorsal rays all simple 

 and jointed ; anal rays branched at the tips, like those of Trachinus ; 

 ventrals before the pectorals of one spine and five jointed rays. 

 Head depressed ; eyes large, prominent, partly on the dorsal aspect, 

 near together ; mouth protractile, and when thrust out the upper 

 ends of the maxillaries project upwards like spines. Branchioste- 

 gals seven. Teeth setaceous, in villiform bands on the premaxil- 

 laries, mandible, anterior corners of the vomer, pharyngeals 

 above and below, and palatines. Tongue and isthmus of the gills 

 smooth. Head unarmed, together with the body, scaly. A row of 

 pores on the preoperculum. Stomach ccecal ; intestine short, making 

 but one flexure ; no pancreatic caeca. One species. 



Genus VIII. Gadopsis, Rich. Aspect of G'aJws. Scales cycloid, 

 extending to the cheeks and gill-covers. A single dorsal with spin- 

 ous rays in front; anal with three spinous rays ; one bifid, jointed 

 ventral ray without a spine, situated far forward on the throat. 

 Head unarmed. Branchiostegals six. Teeth card-like on the pre- 

 maxiUaries, vomer, palatines, and mandible, A fresh-water Aus- 

 tralian fish. 



VOL. XU. 



Genus IX. Aphritis, Cuv. and Valenc. Body elongated. Dorsals Classifica- 

 two, separated. Mouth rather small ; close, short, villiform teeth on tion — 

 the jaws, palatines, and chevron of the vomer. The absence of Acanthop- 

 strong-pointed teeth distinguishes this genus from Percophis; the terous 

 presence of palatine teeth separates it from Percis, and the two dor- Pishes. 

 sals from Oadopsis ; the scales appearing to be ciliated when viewed v , .,,'■- "^ 

 through a lens rather throws a doubt of the propriety of placing the 

 genus in this group. Branchiostegals six. Stomach ceecal ; four 

 pancreatic caeca. A fresh-water Tasmanian fish. 



Genus X. Trichodon, Stel. General aspect of Uranoscopus. 

 Five preopercular spines ; operculum ending in a flat point. Head 

 flat above ; mouth descending almost vertically, and, when shut, hav- 

 ing the mandible in front; eyes lateral, not on the dorsal aspect as in 

 Uranoscopus. No scales. Ventrals thoracic. Cheek not cuirassed 

 by the suborbitars ; teeth in card-like bands (individually slender, 

 pointed, and recurved) on the jaws and front of the vomer, but the 

 palatines are toothless, as is also the tongue. Two dorsals separated 

 by a short interval ; several of the lower pectoral rays simple. 

 Five branchiostegals. One species. 



Genus XI. Sillago, Cuv. Acanthopteri, with along conical head 

 and rather depressed snout, terminated by the fleshy lips of a 

 small mouth. Two continuous dorsals, the second long and low. 

 Upper jaw somewhat protractile, and the mandible articulated con- 

 siderably before the eye ; teeth on the jaws villiform, with an outer 

 row of conical ones. A villiform band on the front of the vomer; 

 preoperculum denticulated on the ascending edge, curving over the 

 throat, so as nearly to touch its fellow. Six branchiostegals. Scales 

 ciliated, covering the opercula, cheeks, and upper part of the head 

 behind the eyes. Cfecal stomach ; pancreatic caeca from two to 

 four; a large forked air-bladder. Ten species. Cuvier is uncer- 

 tain about the proper position of this genus, but thinks that it is 

 most allied to the Sciixnidce with which it might be placed were it 

 not for its vomerine teeth. It is put here at the end of the Urano- 

 scopidce chiefly because no more eligible sitoation offers. 



PERCOIDS. 



Few families of fish have bepn more fully investigated by 

 ichthyologists than this one, yet the vast number of spe- 

 cies that belong to it is embarrassing to students, and the 

 strong external characters which many possess have with- 

 drawn the attention from the more important varieties 

 of structure, to slight serratures of the opercular bones, 

 or the greater or smaller size of the scales on some parts 

 of the head, and other slight modifications of the sur- 

 face, which are obvious to the eye indeed, and therefore 

 useful for subdividing a genus containing many species, 

 but are not of themselves sufficient to establish generic 

 groups or other divisions of higher importance. These 

 comparatively unimportant external characters have how- 

 ever been too generally employed for this purpose, and the 

 importance of the want of teeth on the roof of the mouth 

 having been too rigidly insisted upon, as a variety of struc- 

 ture of family rank, has caused the wide separation of spe- 

 cies nearly connected by aspect, habits, and general confor- 

 mation. Many Percoids have been placed with the Sciae- 

 noids merely because the minute teeth of the palate are 

 early deciduous. On the other hand, forms have been 

 brought together by a ^ew technical characters which have 

 comparatively little natural affinity, and an ichthyologisc 

 who is intimately acquainted with ichthyic anatomy has a 

 wide field before him where he may render great service 

 by reducing the at present heterogeneous assemblages to 

 more fitting order. In the mean time we shall, with a few 

 exceptions, follow our principal autliorities — Miiller for the 

 general arrangement, and the Histoire des Poissons for the 

 generic groups. We have found it convenient to intro- 

 duce into our table, as distinct families, the Percoids of 

 Cuvier which have more or fewer branchiostegals than 

 seven ; or whose ventrals vary in composition from the 

 normal number of five articulated rays, or depart from 

 their usual position in this family under the pectorals. The 

 useful analytical table given in the Histoire des Poissons, 

 abbreviated by the removal of these groups, will remain as 

 follows : — 



2 m 



