ICHTHYOLOGY. 



33 



been destroyed. The chyle produced by the digestion 

 of fisljs is received by absorbing vessels, which ter- 

 minate immediately in the veins, without going 

 through glands. Although most fishes lay eggs, 

 which are matured and hatched out of their body, 

 there are cartilaginous fishes which are viviparous, 

 That there are hermaphrodites among fishes has been 

 lately proved ; for Home has found in lampreys both 

 spawn and milt The productive power of fishes is 

 greater than that of any higher animal. In the 

 spawn of the tench there have been counted 38,000 

 eggs at once ; in that of the mackerel, 546,000 ; and 

 in that of the cod, 1,357,000. The twelfth sign of the 

 Zodiac is called " The Fishes." 



ORDER I. ACANTHOPTEllVGIANS. 



This order comprehends by far the most numerous race of 

 fishes. They are distinguished by the spines which supply the 

 place of the first rays of their dorsal fins, or which alone support 

 the first fin of the back, where there are two ; in some species, 

 instead of a first dorsal fin, it is represented by a few uncon- 

 nected spines. The first rays of their anal fins consist of 

 simple spines, snd each ventral fin has usually one. 



FAMILY I. PEBCOIDES. 



Body oblong, covered with rough and hard scales; opercu- 

 lum or preoperculum, and frequently both, have dentated or 

 spinous margins ; jaws, fore-part of vomer, and palatine bones, 

 provided with teeth. 



DIVISION I. PERCOIDES THORACICI. 



Ventral fins inserted under the pectorals. They are all edi- 

 blp, wholesome, and agreeable to the taste. 



Sub-division 1. Branchiae with seven rays; back with two 

 fins, teeth small and dense, as the pile on velvet. 



1'erca granulata, pi. 46, f. 14. Preoperculum dentated ; bony 

 operculum ending in two or three points; tongue smooth: 

 sub-orbital and humeral in some, slightly dentated ; snout de- 

 void of scales ; second dorsal fin hardly longer than the first; 

 ventral fins placed on the thorax. 



Pomatomus telescopicum, pi. 47, f. 22. Two separate dorsal 

 fins ; preoperculum simply striated, and the operculum emar- 

 ginate; eye excessively large; teeth very small, resembling 

 the pile on velvet. 



Sub-division 2. Having two dorsal fins; long pointed teeth 

 intermixed with the small densely set teeth, like the pile on 

 velvet. Diplorfon maculata, pi. 47, f. 35. 



DIVISION II. 



With seven branchial rays and one dorsal fin. 

 Sub-division 1. With seven branchial rays and one dorsal 

 fin ; teeth dense as the pile on velvet. 



DIVISION III. 



With less than seven branchial rays. 



Sub-division \. One dorsal fin ; some species with hooked 

 teeth interspersed among the dense ones. 

 Sub-division 2. Without interspersed hooked teeth. 

 Sub-division 3. Six branchial rays ; and two dorsal fins. 



DIVISION. IV. 

 With more than seven branchial rays. 



SUB-FAMILY I. PERCOIDES JUGTJLARES. 

 With the throat further forward than the pectoral fins. 



DIVISION V. ABDOMINAL PERCHES. 

 Ventral fins placed further back than the pectorals. 

 Sub-nivisioni Ventral fins entirely behind; pelvis separ- 

 ated from the shoulder bones. 



FAMILY II. MAILED CHEEKS. 



Head variously mailed, and protected by several bony pro- 

 cesses. Suborbital bones more or less extended over the cheeks, 

 articulating behind with the preoperculum. 



Trigla pint, pi. 46, f. 3. Teeth dense, as the pile on velvet, 

 in the jaws, placed before the vomer; pectoral fins large, but 

 not so much so as to enable them to fly in air. 



Certhalacanthes spinarella, pi. 47, f. 15. Formed nearly like 

 the flying Gurnards, particularly in the head, but destitute of 

 supernumerary fins. 



Seorpcena Scropha, pi. 47, f. 30. Head mailed, and rough- 

 ened and compressed on the sides ; body coveted with scales ; 

 branchiae with several rays ; back provided with a single fin ; 

 inferior rays of the pectoral tins, simple, articulated, but not 

 branched. 



T&nianotes tricanthus, pi. 47, f 23. Body much compressed ; 

 dorsal fin very high, and united to the caudal. 



dpistus marmoratus, pL 47, f. 19. Palatine teeth and dorsal 

 fin, as in the scorpions ; rays of the pectoral fins branched : 

 they have a suborbital fin inclining from the cheeks. In the 

 first division the body is scaly, others possess ordinary pec- 

 toral fins, without free rays. 



Oreosoma coniferum, pi. 47, f. 12. Body above and beneath 

 studded with protuberant horny cones, four on the. back and 



ten on the abdomen, arranged in a double series, with scvernl 

 smaller intermediate ones. 



Intermediate betwixt this and the next family Cuvier places 

 a small oval fish, whose whole body is thickly beset with hill- 

 like protuberances, four on the back and ten on the abdomen, 

 arranged in double series, with smaller intermediate ones. 

 Inhabits the Atlantic. 



FAMILY III. SCIENOIDES. 



Preoperculum dentated ; operculum spinous j vomer and 

 palatines destitute of teeth; cranial and facial bones generally 

 cavernous ; muzzle more or less gibbous ; ventral fins fre- 

 quently scaly. Some are provided with two, and others with 

 only one dorsal fin. 



Eques Balteatus, pi. 47, f. 24. Body elongated and compress- 

 ed ; teeth small and thickly set ; first dorsal fin elevated, second 

 long and scaly. 



Heliasus frenatus, pi 47, f. 31. Teeth and opercular pieces, 

 likH those of the Dascyllus, the former small and as densely set 

 as the pile on velvet. 



Sub-diviiion 1. Two dorsal fins. Sphyreenu maculata, pi. 

 47, f. 7. 



Scicena aquila, pi. 46, f. 1 . Destitute of canini and cirri ; 

 pines of anal fin weak. 



Sub division 2. One dorsal fin; with seven branchial rays; 

 >reoperculum dentated. 



&iib.dtvision 3. With less than seven branchial rays, and an 

 nterrupted lateral line. 



FAMILY IV. SPAROIDBS. 



Palate destitute of teeth ; covered with scales, but none on 

 the fins ; muzzle not gibbous, nor bones of head cavernous, des- 

 titute of spines on the operculum, and indentations on the pre- 

 operculum; pylorus provided with caeca! appendages; have 

 never more than six branchial rays. Divided according to the 

 form of their teeth. 



Sub-division l. Sides of the jaws provided with round molars 

 in the form of pavement. 



Pagelus ceiitt oaontus, pi. 46, f. 9. Two rows of small rounded 

 molars in each jaw ; front conical teeth slender and numerous ; 

 iiHiz/.lt' elongated. 



Hub-division 2. Conical teeth on the sides of the jaws, usually 

 in a single range; some of the anterior are drawn into large 

 hooks. 



Sub-division 3. Teeth dense and short, as the pile on velvet ; 

 bent and crowded together like cards around the jaws in some, 

 external row strongest. 



Sub-division 4. Teeth trenchant. 



FAMILY V MENIDES. 



Differing from the former families, in the upper jaw being 

 extremely extensible and retractile, oiving to the length of the 

 intermaxillary pedicles, which withdraw between the orbits; 

 body scaly. 



Smarit Vulgaris. Destitute of teeth in the vomer. 



FAMILY VI. SQUAMIPENNES. 



The soft, and in seme instances the spinous parts of their 

 dorsal and anal tins covered with a scaly incrustation. Body 

 usually greatly compressed ; teeth long, thin, bristle-shaped, 

 and collected in several close rows like the hairs of a brush. 



Ephippus Orbis, pi. 47, f. 25. Dorsal fin deeply emargi noted 

 between its spinous and soft portions ; spinous part destitute 

 of scales. 



Holacanthut ciliaris, pi. 46, f. 20. Preoperculum dentated 

 on the edges, and provided with a large spine at its angle , 

 general lorm, oval or oblong. 



FAMILY VII. SCOMBEROIDES. 



Scales small, body smooth, cseca numerous, and often united 

 in clusters ; with a very powerful tail and caudal fin ; first dor- 

 sal fin entire, last rays of the second, and those of the aunl, 

 detached, forming spurious fins spotted. 



Scomber nuiculosus, pi. 46, f. 6. Body fusiform, covered with 

 uniform and small scales ; tail with two small cutaneous crests 

 on its sides ; a void space between the first and second dorsal 

 fins. 



Xiphias gladius,\A. 46, f. 11. Snout horizontally flattened, 

 and cutting like the blade of a broad-sword. Sides of tail much 

 carinateci; one dorsal fin. 



Xipntas gladius, pi. 46, f. 11. Scales extremely small, and 

 having carinse on the sides of the tail ; provided with a long 

 ensiform beak, which terminates the upper jaw, being an 

 elongation of the voraer and intermaxillaries, supported at its 

 base by the aethmoid, frontals, and maxillaries; branchiae not 

 pectinated ; each of them being formed of two large parallel 

 laminae, with a reticulated surface. 



Cybium lineolatum, pi. 47, f. 36. Destitute of corslet, and 

 body elongated; compressed; cutting teeth resembling lancets; 

 palatine teeth as thickly set as the pile on velvet. 



Zeus faber, pi. 47, 1. 34. Dorsal fin emarginate, its spinet 

 accompanied by long slips of the membrane ; both dorsal and 

 anal fins having a series of bifurcated spines along their base*. 



FAMILY VIII. T.SNIOIDES. 



Body elongated, flattened on the sides ; scales very small. 



Sub-division i. Muzzle elongated : mouth cleft, and armed 

 with strong, pointed, cutting teeth; lower jaw advancing be- 

 yond the upper one. 



Lepidopta argyretts. Ventral fins consist of two small scaly 

 plates, body thin, elongated, provided with a dorsal fin, which 

 c2 



