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as the nidulus of the foi-nix. The general direction of the 

 processes seems to be latero-caudad. An exactly similar 

 group of cells appears in the medulla with the ventral 

 longitudinal tracts and these two niduli are more or less 

 united and may be regarded as outlying accessory niduli of 

 that tract, a view which is confirmed by the motor facias of 

 the cells. 



In sections at a little higher (dorsad) level than the 

 chiasm the cells are massed in great numbers in the ceph- 

 alad part of the tuber cinereum, constituting a more or less 

 definite nidulus. The cells are of the fusiform bipolar 

 variety, and lie with their axes dorso-ventrad and fibre- 

 tracts continuing their dorsal projections. This nidulu^. 

 continues dorsad for some distance, while retaining its 

 relative position about the ventricle. 



A conspicuous nidulus lies immediately entad of the 

 zone of opaque gelatinous substance forming the inner 

 boundary of the optic tract (substantia nigra?). The posi- 

 tion of this cell group is indicated in Plate II, Fig. i a, and 

 Plate I, Fig. z a. The general appearance of these cells is 

 illustrated on Plate II, Fig. 12. They are of the so-called 

 motor type, being susceptible to stain and of pyramidal 

 form, while their apical processes extend entirely through 

 the substantia nigra. The cells are narrow and produced, 

 with the long axis in the ento-ectal direction. At right 

 angles to these cells are others of the fusiform type, with 

 clear large nuclei. It seems quite certain that the ental 

 fibres from the above described pyramidal cells pass ceph- 

 alad, while the peripheral fibre of each seems to fuse with 

 the optic tract. The substantia nigra is itself divided into 

 two portions, causing a similar division of the nidulus, due 

 perhaps to the entrance of large blood-vessels separating a 

 more dorso-caudad portion from that forming the lenticular 

 sheet just entad to the optic tracts. 



Of the cranial nerves derived from the cephalad part 

 of the brain, only the following jottings on the olfactory 



