OF DENISON UNIVERSITY. 43 



much more angular and irregular than the equally large cells of the 

 third nidulus. The nidulus of the fourth also lies immediately dorsad 

 of the dorso- median fasciculus under the aqueduct, but considerably 

 caudad of the third. It is not in contact with the nidulus of the third, 

 neither is it separated from it by fibres of the dorso-median fasciculus, 

 as in Arctomys (Vol. V, Plate X, Fig. i.) The fibres take the usual 

 course to the value of Yieussens. The course of the fifth has not been 

 traced in detail. The sixth nerve springs, as in Arctomys (Vol. V, 

 Plate XVII, Fig. 2,) from a small nidulus in the loop formed by the 

 genu of the seventh. Its fibres descend in several fascicles to a com- 

 mon exit. The seventh takes the usual course, passing first to the 

 genu, which projects into the ventricle entad of the nidulus of the 

 sixth, then turning abruptly ventrad in many strands to its nidulus in 

 the ventral part of the medulla. The course of the eighth agrees pretty 

 closely with Arctomys, as described by Prof. Tight in Vol. V, pages 

 58 and 59. The nidulus of the root of the eighth nerve lies cephalad 

 and dorsad of most of the fibres as they enter the medulla. The 

 fibres of the most cephalic portion of the root pass through this nidu- 

 lus and into the cerebellum. A little farther caudad fibres pass di- 

 rectly mesad under the caudal cms of the cerebellum as it enters the 

 restiform body, some turning up into the cerebellum, some passing 

 farther mesad toward the ventricle. Farther caudad these fibres pass 

 through Deiter's nidulus, then mesad to the eminentia acustica. 

 Deiter's nidulus lies immediately entad of the cms of the cerebellum 

 at this point, with large deeply staining multipolar cells. Still farther 

 caudad the great mass of the fibres of the eighth pass up and arch over 

 the crus of the cerebellum directly into the eminentia acoustica, 

 1 )eiter's nidulus having disappeared. The ninth and tenth roots are 

 as hard to distinguish internally as externally. Their fibres pass dor- 

 so-rnesad to a nidulus near the floor of the ventricle. The eleventh 

 was not traced. The twelfth niduli lie immediately below the ventricle 

 at the region of the calamus scriptorius. Their large multipolar cells 

 lie in a clear stroma, and the two niduli are confluent in the meson. 

 The fibres descend in many bundles to their exits, passing by the 

 olives on the cephalo-lateral aspects of the latter. 



