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HAVE FISHES MEMORY Studies as to the mental powers of animals have already been made on several occasions but only recently have inquiries been made as to whether fishes have a memory or not Uesults have shown traces of a memory Iwth in coral zoophytes and other denizens of the deey Experiments have been made with several fishes but the most striking results have lxMn obtained with a gray perch which lives cliiefly on a small silveryhued sardine Some of these were taken and colored red and were then imt into the tank where the perch was with sev ¬ eral other silvercolored sardines Of course the normal ones were at once attacked and eaten but it was not till hungry that the perch made a ten ¬ tative ineal off one of the redcolored victims on recognizing the sardine flavor however he promptly demolished the remainder Subsequently the speci ¬ mens In the tank devoured tie sardines irrespective of color thus showing not only traces of a memory but also the power to differentiate color Subse ¬ quently sardines colored red and blue were placed in the tank together with the silver ones the same fcceue was repeated the blue ones not being at ¬ tacked till the others were eaten and hunger com ¬ pelled investigation of the newcomers After this introduction the perch ate the sardines of all three types without any difficulty Some spines of the sea nettle actinia were then fastened to the blue sardines these were at once avoided by the perch who promptly got out of the way off the new ¬ comers This showed traces of memory as the re ¬ sults of contact with the sea nettle were clearly shown and recognized
