DISIRIBUTIOK OF SPECIE".. 



87 



Table showing the Dislribution of the Species in the DiffercU River-Basins— Cowi'mvuiH. 



From the above taijle, it will be seen that the number of species 

 inhabiting any one river- basin rapidly inereasea as we leave the 

 Athmtic streams for those of the Gulf. The following table shows the 

 arrangement of the speeies from another point of view — omitting refer- 

 ence to the range of the species outside of the thirteen rivers included 

 in this table: 



Known only from the — 



Ohio 



Alabama 



Species. 



ao 



17 



Known only from the — 



Tennessee 

 Illinois . . . 



Species. 

 10 

 14 



