ICHTHYOLOGY. 27 



with a thin skin filled with air ; it floats on the 

 surface of the sea, and occasionally expands eight 

 broad feet or fins to catch the gale. Its skin is 

 covered with a slimy substance, which corrodes 

 the hands that touch it and occasions pain. 



CHAPTER V. 



Of Spinous Fish. 



Q. How are Spinous Fish distinguished ? 



A. Spinous or bony fish are distinguished by 

 their having a complete bony covering to their 

 gills, by their being destitute of lungs, by their 

 bones being sharp and thorny, and by their tails 

 being perpendicular to the body. 



Q. Is this class numerous ? 



A. So much so that it will be impossible in this 

 little treatise, to do more than to notice the most 

 important. 



Q. How is this class divided ? 



A. Spinous fish are divided into prickly finned 

 fish and soft finned fish, and these are again sub- 

 divided into Apodal, Jugular, Thoracic, Abdomi- 

 nal, according to the situation of the fins. 



; ..... ,. . , , i . ., , 



Expands, v. spreads out. 

 Corrodes, v. renders sore. 



