292 PISCES. 



but of one family ; and which, with tlie jaws perfect, have the filaments of the sills 

 arranged in tufts upon the arches. 



In the rest, which include by much the greater number of the True Fislies, the cha- 

 racter emiiloyed b)' Ray and i\rtedi, and taken from the nature of the first rays of the 

 dorsal and anal fiins, funiislies two principal divisions. Tlicse are Malacopterygii 

 (soft fins), in which all the rays, with the occ;isional exception of the first dorsal or the 

 pectorals, are soft or jointed ; and Acanthopterygii (spiny fins), in which the first 

 portion of the dorsal, or first dorsal when there are two, always have spinous rays, and 

 which have also some in the anal, and at least one in each ventral. 



The first of these sub-classes may be divided according to the position of the ventral 

 fins. If these are on the belly, the fishes are Abdominal ; if attached to the shoulder, 

 thev are Siib-bracliinn ; Lind if wanting, they are Apodal . Each of tliese orders com- 

 prises certain families, of which the abdominal ones are very numerous. 



The Spinous Fislies do not admit of this kind of division ; but must be separated into 

 families, the characters of which are, in many instances, well defined. The same gra- 

 dation of fimiilies cannot be traced among Fishes as among Mammalia. Tlius, the organs 

 of sense, and those of generation in some, indicate connexion between Cartilaginous 

 Fishes and Serpents, while the imjjcrf'ect skeleton of others of these fishes indicates a 

 relation to MoUusca and Worms, [though the far more important disposition of the 

 nervous system, cliaracteristic of the type of "\'ertel3rated i\nimals, is still retained. 



The abstract of Cuvier's arrangement of Fishes, by far the best — that is, the most 

 natural, which has hitlicrto Ijeen made, or which there are materials for making — may 

 be given brieflv tluis: — The series of True or Bony Fishes he divides into the two divi- 

 sions already mentioned, as distinguished bv the rays of the fins. Tlie Spinous Fishes 

 form a single order, and this order he divides into fifteen families, whicli he names, 

 from some well-known species as the type, or for some marked peculiarity of character 

 whicli belongs to the wdiole of the family and to no other fish. The Soft- finned Fishes 

 he divides into three orders, according as the ventral fins are abdominal, tlioracic, or 

 wanting; and the Cartilaginous Fishes he divides into two orders, — those with free 

 gills, and those with the gills fixed.] 



THE FIRST ORDER OF BONY FISHES. 



AC.VNTUOrTERYGlI. 



This first order contains by far the greater number of the Ordinary Fishes. Their characters 

 are spinous rays m the first dorsal, if there are more than one, and spinous rays in the first 

 part if there is one only ; but sometimes, instead of a first dorsal, the\' have free s])ines 

 witliout .any connecting membranes. The aniil fin has also its first rays spinous ; and 

 there is generally one such ray in each ventral. [Wlieii -hc speak of tlie first ray of a fin, 

 we mean tlie one nearest the head of the fish, which is easily understood in the other fins, and 

 is the extreme one either above or behjw m the eaudah] 



The sjiinous fishes are .arranged into fifteen t'ainihes, and some of these families coutam a 

 vast number of genera. The families are named, as already noticed, from some well-kiioun 

 g|iecies, or some strikingly peculiar character. [When a species is the type, the teclinical 

 name of the family ends in «te or ojrfff, the Greek word for reseuiblaiiee ; and when it is 

 founded on a peculiar character, the name is descriptive of tliat]. 



