Among some fishes, forwarded by the late Dr. Bleeker to the Leyden Museum, I came across four specimens evidently belonging to the genus Arius, differing however from all known species of that genus. They therefore represent a new species, which I now describe under the name of Arius Bleekeri in honour of the great Ichthyologist, who collected them. The systematic position of this new species is between the two East Indian Arius macronotacanthus Blkr. and Arius coelatus Val. After having described it, I will compare my Arius Bleekeri with these two well-known forms.