[Study of the caudate-cortical projections of the rat and cat brain by the fluorescence labeling method].

Direct caudate-cortical projections have been studied by means of the fluorescent label method. Neither in rats, nor in cats fluorescent neurons have been revealed in the caudate nucleus when primulin is injected into various cortical fields. The negative results obtained do not, however, give enough reasons to repudiate the existance of the direct caudate-cortical projections, since additional experiments performed with injection of a luminiscent dye into other brain structures demonstrate that primulin transport is not always fulfilled.