156 



MARINE PRODUCTS OF COMMERCE 



groupers (Epinephales and Mycteroperca) , snappers (Lutianus), grunts (Hae- 

 mulon), and many others (Figs. 10-8 through 10-12). 



Many spiny-rayed fishes have 2 dorsal fins, however, the first being composed 



(.Courtesy U. S. Fish and Wildlife Service) 



Fig. 10-7. Haddock (Melangogrammus aegelfinus). 



wholly of spines, and the second commonly of 1 spine and a variable ntimber of 

 soft rays. Examples of this type of arrangement are the mullets (Mugil), striped 

 bass (Roccus), croakers (Micropogon) , weakfish (Cynoscion) , etc. (Figs. 10-13 

 and 10-14). 



Still another type of single-rayed fin occurs among some of the spiny-rayed 



{Courtesy U. S. Fish and Wildlife Service) 



Fig. 10-8. Sea bass {Centropristes striatus). 



fishes. Such a structure is known to the ichthyologist as a "finlet". Finlets occur 

 chiefly among the mackerels and tunas and their relatives. These fins are placed 

 behind the second dorsal and anal fin and vary in number from 1 to 10, accord- 

 ing to the species. 



In the vast majority of spiny-rayed fishes the ventral fins are attached to the 



