130 FLORENCE R. SARIN 



The corpus restiforme, or inferior cerebellar peduncle, is med- 

 ullated and is shown as no. 42 in fig. 7. It was not included in 

 the model, nor were the formatio reticularis fibres, nor the cianial 

 nerves, since they were all shown in the previous model and were 

 not necessarj^ here for orientation. The brachium conjunctivum, 

 or superior cerebellar peduncle is, however, included in fig. 1, 

 (no. 45), because of its relations to a possible descending tract 

 from the red nucleus (no. 46). There is a small bundle of fibres 

 (no. 46), emerging from the caudal end of the red nucleus and 

 extending into the pons just dorsal to the lemniscus medialis, 

 near the median line. It cannot be followed far into the pons. 

 Its relations are best seen by comparing fig. 1 and fig. 5. The 

 sagittal sections are not adequate foi determining whether this 

 is a crossed path or not and the fibres cannot be traced below the 

 upper fourth of the pons. 



In connection with the optic nerve (no. 47), there is a tiny bundle 

 of medullated fibres shown at the root of the nerve both in fig. 5 

 and in fig. 7. Its connections could not be traced — I thought of 

 a Gudden's commissure, but it neither extended to the mid-line nor 

 to the geniculate body. There is, however, a portion of the optic 

 nerve medullated, as it enters the lateral geniculate body. This 

 bundle is shown in the figure already referred to in Barker's 

 Nervous System. 



The last of these rather indefinite medullated bundles, is the 

 very small portion of the most medial part of the crus in the hypo- 

 thalamic region containing a few medullated fibres. These fibres 

 show in fig. 4, just lateral to Forel's fascisulus (no. 19), extending 

 on the one hand toward the substantia nigra and on the other to 

 the little bundle of medullated fibres (no. 48), that separates the 

 two parts of the globus pallidus near the median line. These 

 fibres are most unsatisfactory for study in these sections. All 

 that can be said is that they lie in the crus between three nuclei, 

 the globus pallidus on the one hand and the hypothalamic nucleus 

 of Luys and the substantia nigra on the other. 



It now remains to describe the relations the various nuclei 

 shown in the model. The nuclei of the mid brain require no special 

 mention except that the form of the substantia nigra comes out 



