ICHTHYOLOGY. 



37 



ORDER III. SUB-BRACHIAN MALACOPTERYOIANS. 



Ventrals placed under the pectorals ; pelvis directly suspended 

 t> the shoulder bones. 



FAMILY I. GADITES. 



Ventrals pointed and attached to the throat ; body slightly 

 elongated, compressed ; scaly; head scaleless; fins soft; jaws 

 imd front of vomer with poiiited teeth, set in several rows, re- 

 sembling a rasp ; branchiae large, seven-rayed : most of the 

 tpci'ies have three fins on the back ; one or two situated be- 

 hind the anal opening and a distinct caudal fin. 



FAMILY II. FLAT-FISHES. 



Head devoid of symmetry ; both eyes on one side, which is 

 always uppermost : two sides of the mouth unequal ; body much 

 rompressed ; dorsal fin generally extending along the whole 

 back, and the anal occupies the under part, appearing as if a 

 continuation of the ventral, which are often united with it. 

 Some of the species have their head reversed from the ordinary 

 law. 



Pin testa Camaria, pi. 46, f. 12. A range of cutting teeth in 

 each jaw, usually appearing as if pared in the pharyngeals ; dor- 

 sal fin extending the length of the eye. An interval between 

 the caudal and dorsal, as well as between the anal. Generally 

 rhomboidal, eyes placed on the right side. 



Solea Zebra, pi. 46, f. 24. Mouth obliqued to the opposite 

 side to that in which the eyes are placed, that side only pro- 

 vided with minute thick-set teeth ; snout rounded, projecting 

 beyond the mouth ; dorsal fin commencing at the mouth, which, 

 with the anal fin extends to the caudal ; lateral line straight ; 

 general form ohlong 



Lamprtt guttitus, pi. 47, f. 9. 



FAMILY III. DISCOBOLI. 



Ventral fins forming a disk. 



Cyclopterus lamput, pi. 47, f. 18. First dorsal fin more or less 

 visible, but very low ; rays simple ; a second branchial ray op- 

 posite the anal fin. 



Echeneis Remora, pi. 46, f. 16. Head provided with a de- 

 pressed disk, composed of transverse lamina 1 , directed obliquely 

 backwards, posterior edge deutated ; body elongated and scaly; 

 a small soft dorsal opposite the anal ; mouth horizontally cleft 

 and rounded ; lower jaw projecting beyond the other, inter- 

 m.ixillariea with teeth resembling those of a card ; a range of 

 delicate teeth skirt the maxillaries; anterior edge of the vomer 

 with small teeth like a card. 



ORDER IV. APODAL MALACOPTERYGIANS. 



There is but one natural family in this order. The species 

 are of an elongated form ; skin thick and soft ; scales in conse- 

 quence nearly invisible ; bones few. 



FAMILY I. 



Anguilla conger. With pectoral fins, and branchiae opening 

 under them on either side ; dorsal and caudal fins continued 

 round the end of the tail. 



Ophidium tetradens. Dorsal and anal fin united with that 

 of the tail, and terminating the body, which is much elongated 

 and compressed, so much so that it resembles a sword in a 

 point ; scales very email, and planted in the thickness of 

 the skin. 



ORDER V. LOPHOBRANCHIATB FlSHES. 



Jaws perfect and free ; gills in place of being like the teeth 

 of a comb, are divided into small tufts ; arranged in pairs along 

 the branchial arches. They are enclosed beneath a farire oper- 

 culum, fixed down on both sides by a membrane, which exhi- 

 bits only a small orifice for the exit of the water, and snowing 

 in its thickness vestiges of rays only ; srutellated plates of 

 mail cover their body, which is usually of an angular shape. 



Syngnathui acus, pi. 47, f. 3. Snout tubular, formed like 

 the flute-mouths, by an elongation of the aethmoid, vomer, 

 tympanals, preopercula, and other bones, terminated by an 

 ordinary mouth, almost vertically cleft. Respiratory opening 

 lear the nape ; devoid of ventral fins. 



Hippocampus foliatvs, pi. 47. f. 10. Trunk laterally com- 

 oresaed, and considerably more elevated than the tail. Junc- 

 tions of scales raised into ridges, and their salient angles into 

 Hii HIM. Tail destitute of fins. 



Pegasus Draco, pi. 47, f. 16. Snout salient ; mouth under 

 its base ; body mailed, as in the Hippocampi ; trunk broad, de- 

 pressed ; branchial apertures placed on the sides ; two distinct 

 ventral fins behind the pectorals, which are frequently large, 

 whence the name of the genus. 



ORDER VI. PLECTOGNATHES. 



Maxillary hone permanently attached to the side of the inter- 

 maxillary, by which the jaw is alone constituted, and in the 

 manner in which the palatine anal is united by its suture to 

 the cranium, and consequently destitute of power of motion. 

 Operctila and rays concealed under a thick skin, through which 

 only a small branchial fissure is visible. They have no true 

 ventral fins. 



FAMILY I GYMNODONTBS. 



In place of teeth a small ivory substance, internally divided 

 Into laminae, which, in their aggregate, resemble a parrot's 

 bill. Opercula small, five rays on each side, all nearly con- 

 cealed. 



Diadon Hiitnx, pi. 47, f. 17. Jaws undivided, formed of one 

 piece above, and another below ; behind the cutting edges of 

 which, a round transversely furrowed portion, acting as an 

 instrument of mastication ; skin provided with pointed spines, 

 resembling, when inflated, the burr of a chestnut tree. 



Tetraodon laspidus, pi. 46, f. 4. Jaws divided in the middle 

 by a suture, presenting the appearance of four teeth, two iibove 

 and two below ; spines small and low. 



Cephalus brevis, pi 46, f. 5. Jaws undivided ; body com- 

 pressed, and destitute of spines ; incapable of inflation ; tail so 

 short and high, that its posterior termination appears as if cut 

 oft' : dorsal and anal fins, both high and pointed, and are united 

 to the caudal. Skin with a thick layer of gelatinous substance 

 spread under it 



FAMILY II. SCLEHODERMES. 



Mouth conical or pyramidical, projecting from the region of 

 the eyes, and terminating in a small mouth, provided with a 

 few distinct teeth in each jaw. Skin generally rough or pro- 

 vided with hard scales. 



Balistes acttleatus, pi. 46, f. 22. Body compressed ; each jaw 

 containing eight teeth, in a single row, generally cutting ; 

 skin scaly, or covered with thickset granulations, but not 

 osseous ; first dorsal fin with one or more spines, articulated 

 with a bone which is attached to the cranium ; the eecond 

 dorsal fin long, soft, and placed opposite to an anal one, which 

 is nearly similar. 



Ostraciun auritus, pi. 46, f. 21, and Ostracion tumtus, pi. 

 47, f. 13. Head and body covered with bony plates, in place of 

 scales, soldered together, forming an inflexible shield ; the 

 only movable parts being the tail, fins, mouth, and a small lip 

 with which the edge of the gills is provided ; all of which pass 

 through orifices in the coat of mail by which they are invested. 

 The vertebral column is also soldered together. Each jaw pro- 

 vided with ten or twelve conical teeth ; external branr-hial 

 aperture, a small slit, provided with a cutaneous lobe. Desti- 

 tute of both pelvis and ventrals ; a small single ventral and 

 dorsal fin only. 



Plata* gaimardi, pi. 47. f. iO. 



CHONDROPTERYGIANS. 



Several of this division approach in their formations to the 

 reptiles, in the conformation of their auditory and genital or- 

 gans. In some, the organization is FO simple, and the skeleton 

 so greatly reduced, that they hardly deserve a place among 

 vertebral animals. They therefore constitute a neries some- 

 what similar to the first, in the same manner as Marsupial 

 animals, bear a similitude to the hoofed Mammalia. 



The skeleton is essentially cartilaginous, containing no osseous 

 fibres, the calcarious matter being deposited in small grains, 

 and not in filaments ; consequently they are destitute of sutures 

 in their cranium, which is always formed of a single piece. 



ORDER I. STURIONES. 



Gills with a single wide opening, and provided with an oper- 

 culum, but destitute of rays in the membrane. 



Acipenser huso, pi. 46, f. 27. Body covered with bony plates, 

 set in a series of longitudinal rows, and mailed on the exterior 

 portion of the head ; the mouth is small and toothless, situate 

 under the snout ; the palatine is affixed to the maxillaries, and 

 inserted into the upper jaw, the vestiges of the intermaxil- 

 laries forming part of the thickness of the lips. The mouth 

 being placed on a pedicle, is more protractile than that of the 

 shark ; eyes and nostrils placed on the side of the head, and 

 there are cirri inserted under the snout ; no appearance of exter- 

 nal ear : a sphericle behind the temple leads to the branchiae. 

 Dorsal fin situated behind the ventrals, and the anal fin under 

 it ; the caudal fin surrounds the extremity of Ae spine, and is 

 provided with a salient lobe beneath. 



Callorhynchus Australis, pi. 46, f. 26. Snoi- 1 terminated by 

 a fleshy, hoe-shaped appendage ; the second dorsa. fin com- 

 mences over the ventrals and terminates at the front part of the 

 fin attached to the tail. 



ORDER II. FIXED GILLED CHONDROPTERYGIANS. 



Organs for the escape of water pierced in the skin, some- 

 times terminating in a common duct, through which the water 

 is transmitted ; little cartilaginous arches are frequently sus- 

 pended in the muscles opposite to the external edges of the 

 branchiae, and which may be denominated branchial ribs. 



FAMILY I. SELACPII PLAGIOSTOMI. 



Palatines and post-mandibularies, only, provided with teeth, 

 and supply the place of jaws, which are represented by mere 

 vestiges of bone ; their apparent jaw suspended by a single 

 bone to the cranium, which represents the tympana!, jugal, and 

 temporal bones, and also the preoperculum : hyod bone affixed 

 to this pedicle, and supports the branchiostegal rays, as in or- 

 dinary fishes, although hardly visible externally ; followed by 

 the branchial arches, but neither compose the operculura. 

 Provided with both pectoral and ventral fins, the latter on the 

 abdomen, placed on each side of the anal opening. 



Squalus Zygtena, pi. 46, f. 8. Snout prominent, with nostrils 

 placed beneath, but neither in a prolonged furrow, nor provided 

 with lobules, having a lobule on the underside of the caudal fin 

 approximating to the bifurcated form. 



Pristit antiquorum, pi. 46, f. 7. elongated with the body flat- 

 tened before, and the branchial opening situated below, as in 

 the ravs ; having a very long, depressed, sword-shaped snout, 



