CALLITHRIX JACCHUS, THE MARMOSET 



169 



trast in size of these nuelei as they lie sibc by side in the dorsal portion of the 

 section (NG, NB). The mesial fillet (Mf) has attained more prominence 

 because of the addition to it of a larger number of arcuate fibers. 



FIG. 02. MARMOSET. LEVEL THROUGH THE MIDDLE OF THE INFERIOR OLIVE. 



DT, Deitcrso-spinal Tract; fle. Dorsal Spinocerebellar Tract; Gow, Ventral Spinocerebellar Tract; hel, 

 Spino-olivary Tract of Hehveg; 10, Inferior Olive; mf. Mesial Fillet; nb, Nucleus of Burdach; ng. Nucleus of 

 Goll; NHV, Hypoglossal Nucleus; nr. Nucleus of Rolando; nvd. Dorsal Vagal Nucleus; N12, Hypoglossal 

 Nerve; pd, Predorsal Bundle; pl. Posterior Longitudinal Fasciculus; py, Pyramid; ref. Reticular Formation; 

 RST, Rubrospinal Tract; spt, Spinothalamic Tract; trd, Descending Trigeminal Tract. [Accession No. 146. 

 Section 37. Actual Size 8X4 mm.] 



LEVEL OF THE AESTIBULAR NUCLEI AND TUBERCULUM ACUSTICUM (fIG. 83) 



At the level of the vestibular nuclei and tuberculum acusticum, the 

 cross sections are characterized by the wide separation of the lateral walls 

 of the fourth ventricle and the appearance of the vermis cerebelli in 

 relation with the ventricle. In the position formerly occupied by the nuclei 

 of Goll and Burdach are two prominent nuclear masses intimately concerned 



