344 



rolling to (hat side was observed. Also it strikes us that in both 

 cases, no trace of degeneration in the P.L.B., and the F.D.A. was 

 found. Also in an other experiment the degeneration is found in the 

 Ramus descendens and also this animal made in the latter days of 

 its life rolling movements to the healthy side. 



Also after sagittal lesions, immediately lateral to the P. L. B., I 

 observed a tendency to fall on the normal side. In this point case 

 146 and 158 complete each other very well. In 158 the extensive 

 sagittal lesion cuts otf the whole of the Deiters Complex from the 

 raphe; in 146 the smaller and more caudal sagittal lesion begins 

 exactly distally from tlie striae acusticae (Monakow). In both cases 

 during a longer (158) and shorter (146) period a tendency to fall 

 to the normal side was noted. Only in the proximal lesion we find 

 the degeneration in the medial part of the F. D. A. In 146 nor in 

 the Ramus descendens nor in the F. D. A. a sufficient degeneration 

 is found, to be held responsible for the "Slight tendency to fall to 

 the right side" as was noted some days after the operation. It may 

 be supposed, that the sagittal haemorrhage on the lateral side of the 

 P. L. B. by mechanical compression should have interfered with the 

 function of the Ramus descendens and the Nuc. Deiters, irritating 

 it, but not causing the dissolution of medullary sheaths. In the case 

 of 158 in accordance with the crossed ascending vestibulo-mesen- 

 cephalic bundle in the P. L. B. during 9 days circus movement to 

 the normal side was noted; in 146 only during a few days some 

 tendency to it. That the crossed ascending vestibulo-mesencephalic 

 bundle not exclusively must be limited to the areal of the P. L. B. 

 proper, we find confirmed not only in 158, but also in 113. 



The cases, which we have combined in group IV, (direct lesion 

 of the P. L. B. system) can be divided after the physiological data 

 into 2 subgroups. The fii'st subgroup contains 7 animals, which during 

 several days performed rolling movements to the side of the lesion. 

 In all these animals the F.D.A. w^as either directly hurt by the 

 lesion or was found in a decided state of degeneration, viz. as a 

 result of lesion in the region immediately oral to (he DEiTERS-com- 

 plex. The black granules as a proof of an intense ascending dege- 

 neration (descending fibres are never found in the F.D.A.) we find 

 only in 92, 93 and N". 3 (Series of Besta) spread over the whole 

 area ; in the other cases exclusively the lateral half of the F.D.A. 

 is found degenerated, in 3 cases as a result of direct traumatical 

 destruction of that part. Very instructive is in this I'egard 150, 

 where exclusively the most lateral part of the F.D.A. was hurt 

 about the Corpora (juadrigemina posteriora, together with parts that 



