Abstract
The purpose is to study the starting points of efferent fibres from each part of nucleus lenticularis especially descending fibres reaching to nuclei of the midbrain. Dividing the cat nucleus lenticularis into five parts and making electrically cauterized lesion in each part, the secondary degeneration was studied by Marchi staining.
1) After lesion of dorsal part of the pallidum the degenerated granules were found in the nucleus thalami lateralis ventricularis at isolateral side, luys body, Forel area, substantia nigra, red nucleus at both side and nucleus interstitialis Cajali. The secondary degeneration was more marked on the isolateral side.
2) After lesion of ventral and lateral parts of the pallidum, stronger degeneration was proved though the degenerated part was almost the same as 1). No difference was seen between the both parts.
3) The fibres starting out from the pallidum and apparently communicating with the opposite side consisted of fibres passing Forel and Meynert crossing and reaching to red nucleus and nucleus interstitialis Cajali and also fibres passing the back conjunction and reaching to nucleus interstitialis Cajali.
4) After lesion of dorsal side of the putamen the degenerated fibres were found in the middle and ventral part of the pallidum. Further descending, the degenerated granules were found in substantia nigra on the isolateral side a little.
5) After lesi n of ventral inner part of the putamen only small degenerated granules were found in ventral outer side of the pallidum.
6) No degeneration was found in the fibres starting from the putamen and reaching the opposite side.
