KEY TO THE PRINCIPAL FISHES 



T89 



of the head, or, as in aa, whether they are on its lower surface. 

 As they are in the former position, we continue with b. There 



£ad& flau 



Mud JSAa.te 

 Fig. 59. — Teeth of Sharks and Rays. 



are two dorsal fins in our shark, so we skip to bb, and then 

 pass on to d. The character given under d will not fit our 

 shark, so that we have to skip again to dd, and then read on 

 with r. The body is not broad or depressed, and the pectoral 



