236 C. JUDSON HERRICK 



coarse and heavily myelinated, lie in the deepest layer of the 

 stratum albmn (figs. 9 to 14, r.V.mes.). This nucleus and 

 root can be readily identified in both Weigert and Cajal 

 preparations. 



4. The nervus terminalis 



The central course of the nervus terminalis of Necturus has 

 been described by McKibben ('11), and I have confirmed his 

 description in every particular. These unmyelinated fibers 

 enter the brain at the ventral border of the olfactory bulb and 

 pass backward in many slender fascicles in a very superficial 

 position along the ventral border of the cerebral hemisphere 

 and ventro-lateral border of the diencephalon, as far as the 

 tuberculum posterius in the cerebral peduncle. Some of these 

 fascicles decussate in the anterior commissure, in the postoptic 

 commissure, and in the commissure of the tuberculum posterius. 

 The mesencephalic fibers apparently end in the immediate vicin- 

 ity of the commissure of the tuberculum posterius. 



5. The parietal nerve 



The epiphysis of Necturus has been described by Kingsbury 

 ('95, p. 160) and its development has been studied by Warren 

 ('05). It is a hollow epithelial vesicle, whose ca\dty presents 

 numerous diverticula formed by incomplete epithelial septa. 

 In early developmental stages this cavity becomes completely 

 separated from the diencephalic ventricle by the occlusion of 

 the cavity of the epiphyseal stalk. 



The parietal nerve of Necturus was seen by Kingsbury, who 

 writes ('95, p, 161): "Two or three myelinic nerve fibers, on 

 each side, were found to pass to the ectal surface of the brain 

 and disappear after turning mesad beneath the epiphysis. They 

 came from the mesencephal to which they could be traced 

 caudad." 



To this description I can add some further details without, 

 however, reaching a satisfactory interpretation. The number 

 of myelinated nerve fibers connected with the epiphysis in our 



