108 CLASS-BOOK OF ZOOLOGY. 



§ 458. That the Romans and Greeks were great lovers 

 of fish, is shown by many facts. For instance, in Athens 

 a fine horse was given for a peculiar kind of fish ; and 

 in Rome, often much more. The wealthy family Licinia 

 was honored by the name of Murana, (Eel,) and the cele- 

 brated epicure Sergius with that of Orata, (Gold-fish,) 

 on account of their love of fish. The dinner-table of the 

 Roman emperor Theodoric the Great, (in the sixth cen- 

 tury.) was daily covered with a great variety of costly fish. 



§ 459. As the systematic classification of fishes appears 

 to stand in need of much improvement, we make use 

 here of the system of Linnaeus, the most comprehensive 

 for beginners ; he divided Fishes into the six following 

 Orders, viz. : 



1st Order. — Cartilaginous Fishes with open gills : 

 (Chondropterygii.) 



2d Order. — Cartilaginous Fishes with covered gills : 

 (Branchiostegi.) 



3d Order. — Apodal Fishes, (Apodes :) without ventral 

 fins. 



4th Order. — Jugular Fishes, (Jugulares :) having the 

 ventral in front of the pectoral fins. 



5th Order. — Thoracic Fishes, (Thoracici :) having the 

 ventral immediately below the pectoral fins. 



6th Order. — Abdominal Fishes, (Abdominales :) hav- 

 ing the ventral behind the pectoral fins. 



1st Order. — Cartilaginous Fishes with open gills. 



Fig. 25. 



The Hammer-headed Shark. — (Squalus Zygoma.) 



