SUMMARY1) The soluble protein taken from the cerebral hemisphere of dogs was fractionated by the methods ofTiseliuselectrophoresis, paper electrophoresis and sodium sulfate. Difference among the results of the three fractionating methods was subjected under discussion.2) No large difference in the electrophoretic patterns among the cerebral lobes was detectable, but there availed a significant difference between the grey matter and the white matter. There was established no essential difference in the electrophoretic patterns of cerebral hemisphere of mice, dogs, the bovine and the human, in spite of certain difference existent among respective fraction ratio according to the animal spec