202 ZOOLOGY. 
The classification of Cuvier is the one more generally adopted. He 
divides the entire class into bony and cartilaginous ; the former again into 
spinous rayed and soft rayed ; the latter into those with free gills, and such 
as have them fixed. We have here zoom only for the Orders and Families. 
J. Acanruopreryera. Fin rays spinous. 
Percide. Cheetodontide. Mugilide. 
Triglide. Scombride. Gobide. 
Scienide. Teuthide. Lophide. 
Sparide. Tenide. Labride. 
Menide. Atherinide. Siluride. 
I]. Matacorreryen AspominaLes. Fin rays soft. Ventrals behind the 
pectoral. 
Cyprinide. , Fistularide. Clupeide. 
Ksocide. Salmonide. 
[I]. Mazacoprerven Susppracurati. Fin rays soft. Ventrals beneath the 
pectoral. 
Gadide. Cyclopteride. Kchineide. 
Planide. 
IV. Matacorrerven Apopa. Fin rays soft. Ventrals wanting. 
Anguillide. 
V. Lopuosrancuy. Gills in tufis ; not pectinate. 
Syngnathide. 
VI. Puectroenatui. Bones of the head closely combined. 
Gymnodontide. Balistide. Ostracionide. 
VII. Cuonproprervert Brancuus Liseris. Gills pectinate, free. A single 
gull opening. 
Sturionide. 
VIII. Cuonprorteryen Branenus Fixis. Gill apertures more than one 
on each side. Gulls not free. 
Squalide. Raiade. Petromyzonide. 
A highly philosophical classification is that of Prof. Agassiz, which is 
especially applicable to the arrangement of fossil forms. This eminent 
naturalist divides fishes into four Orders from characters derived from the 
scales. They are as follows: 
I. Puacoiws. Characterized by having the skin provided with osseous 
plates of various sizes and numbers, as in the sharks, rays, &c. The 
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