182 ZOOLOGY. 



Isinglass ; but some have it of a very superior quality to others ; 

 they are most abundant in northern countries ; frequenting 

 the mouths of rivers, particularly at their influx with the sea, 

 they feed on small fish, moluscas, and insects ; they are taken 

 by the hook or in nets. 



9. Lophius. Angleb. Head and body large, flat, circular ; 



tongue broad ; teeth numerous, small, situated in the 

 jaws, tongue, and palate ; one breathing aperture be- 

 hind each ventral Jin ; pectoral fins broad and thick. 



10. Cyclopterous. Sucker. Head obtuse; teeth small, 

 sharp, numerous ; gilL membrane with four cartilagi- 

 nous rays j body thick ; back arched ; ventral fins 

 united. 



11. Balistes. File-Fish. Head compressed, in some spe- 

 cies with a spine between the eyes ; mouth narrow ; 

 teeth eight in each jaw ; of which the two anterior ones 

 are the longest ; breathing aperture narrow, placed 

 above the jjec^ora/^M* ; gill membrane with two carti- 

 laginous rays ; body compressed, roughened with mi- 

 nute prickles. 



12. Ostracion. Thunk-Fish. Teeth round, blunt, pointing 

 forwards ; aperture linear ; body encased in a com- 

 plete bony covering ; ventral fins wanting. 



13. Diodon. Jaws bony, entire; aperture of the gill» 



linear ; body covered on all sides with long, sharp, 

 strong, moveable, hollow spines. 



