OF DENISON UNIVEkSlTV ^q 



which we will consider, is the large nucleus of the seventh nerve seen 

 at a. This nucleus occupies a ventrolateral position and is (juite large 

 with fibres passing from the cells collected into definite fasciculi, 

 which pass dorso-cephalad almost to the floor of the ventricle where 

 they are united into two or three large bundles and turn upon them- 

 selves, forming the knee of the seventh nerve, seen in cross section, 

 (Plate XVII, Fig. i, /, and Fig 2, b.) The cells of this nucleus are 

 of the multipolar type, with numerous processes and large nuclei. 

 l^hey measure about .07 mm. in length with nucleus. 01 mm. in diame- 

 ter. A magnified view of a small portion of the nucleus is shown by 

 Fig. 4, Plate XVI. Fig. 6, of same plate shows at e, the position of 

 the large fascicle of the seventh seen in cross section. 



Before leaving the eighth root, it is well to examine one more sec- 

 tion taken farther towards the cephalad margin of the root. Plate 

 XVIII, Fig, I, at a, represents the entrance of the fibres, with the 

 root nucleus at b. In this section the restiform body has passed into 

 the cerebellum to the vermiform process (Ranney), and the fibres of the 

 eighth are not here divided, but pass directly mto Deiter's nucleus and 

 upwards into the cerebellum, while the internal nucleus is reduced to 

 a very small cluster of small cells. That fibres of the eighth pass into 

 the cerebellum is without question. We observe also at this level the 

 nucleus of the sixth at^, and the forward extension of the olivary body 

 at e. The formatio reticularis comprises the largest part of the section. 



Examining a section at the level of the entrance of the seventh, 

 (Plate XVII, Fig. 2,) we are able to trace the large bundle of the sev 

 enth, a, through the formatio reticularis above and medianly to the nu- 

 cleus of the sixth, d, to its flexure or genu. In the same manner the 

 path of the fibres of the sixth nerve are easily traced to their nucleus, 

 d, on the floor of the ventricle. The cells of this nucleus are about 

 .05 mm. in length and have their axes in the direction of the entrance 

 of the fibres into the nucleus. (Plate XVII, Fig. 5.) The olivary 

 body, c, is also [present in this section as a nucleus on the ventral side 

 of the medulla, its cells measure about .02 mm. and have numerous 

 processes which start abruptly from the cell, thus giving them an even 

 oudine in appearance under a low power There is a very evident 

 decussation with its fellow of the opi)()sirt' side. Fii:. 1. Plate X\ III, 

 gives a magnified view of these cells. 



The next section considered is taken at the level ut the caudad 

 margin of the fifth root, (Plate XVIII, Fig. 3.) The .scale upon which 



