ALESTES. 



Ill 



line are short and usually simple, though sometimes provided with a short downward 

 branch. 



The pectoral and ventral fins are always acutely pointed ; the rays in the former 

 number fifteen, in the latter ten. 



. Kir. 17. 



JL. B. C. 



Detached scales of : A. Alestes dentex ; B. A. nurse ; C. A. macrolepidotus. 



Although the teeth in the upper jaw are really in two series, there may appear to be 

 three, as observed in A. nurse by Dr. Gunther, who remarks : — " In old examples the 

 second tooth of the front series of each side is generally placed a little backwards, 

 as if there was not room enough for it between the first and third teeth ; and there 



Fig. 18. 



M. 



Upper views of skulls and inner views of jaws of : A. Alestes dentex, and E. A. macrolepidotus. 



always remains a free space indicating the original place which it had occupied at an 

 earlier age." 



As regards the skull, the species inhabiting the Nile fall into two groups : — One 



