i86 



THE NERVOUS SYSTEM 



130). One of these masses, the dorsal cochlear nucleus, is placed on the dorso- 

 lateral aspect of the restiform body and produces a prominent elevation on the 

 surface of the brain (Fig. 91). The other, known as the ventral cochlear nucleus, 

 is in contact with the ventrolateral aspect of the restiform body. 



Secondary Auditory Path. From the cells of the ventral cochlear nucleus 

 arise fibers which stream medialward in the ventral part of the pars dorsalis 

 pontis and form the trapezoid body (Figs. 108, 134). The fibers cross the median 

 plane and on reaching the lateral border of the opposite superior olivary nucleus 

 turn rostrally as a compact bundle known as the lateral lemniscus (Figs. 110, 



Fig. 133. Section of the spiral ganglion and organ of Corti of the mouse: A, Bipolar cells of 

 the spiral ganglion; B, outer hair cells; C, sustentacular cells; D, terminal arborization of the 

 peripheral branch of a bipolar cell about an inner hair cell; T, tectorial membrane. Golgi method. 

 (Cajal.) 



112, 114). Some of the fibers of the trapezoid body end in the superior olivary 

 nuclei and in the nuclei of the trapezoid body, while others give off collaterals to 

 these nuclear masses. Some of the fibers arising in these nuclei, especially in 

 the nuclei of the trapezoid body, join in the formation of the lateral lemniscus; 

 but according to Cajal (1909) a majority of the fibers from the superior olivary 

 nucleus belong to short reflex pathways in the reticular formation connecting 

 the cochlear nerve with the nuclei of the motor nerves of the head and neck. 

 Fibers arising in the dorsal cochlear nucleus, and possibly also some from the 

 ventral cochlear nucleus, sweep over the dorsal surface of the restiform body 

 and the floor of the fourth ventricle as the s trice medullares acusticce. These may 



