326 S. Simpson, 



generated crusta. What particular region of tlie cortex tliey take 

 origin from has not been determined and what their significance is I 

 am unable to say. It may be that they are indirectly connected 

 through the grey matter of the anterior corpora quadrigemina with 

 the nuclei of the nerves of the eye muscles situated in this region 

 (nuclei of S^'"! and 4*^ nerves); that is, short neurones may be inter- 

 polated between the terminations of these fibres in the anterior cor- 

 pora quadrigemina and the cells of origin of the fibres of the oculo- 

 motor and trochlear nerves. In this connection it will be interesting 

 to determine whether they come from the "head and eyes" area of 

 the motor cortex. Another possibility is that they end in relation to 

 the cells of some other tract or tracts which take origin in the anterior 

 corpora quadrigemina and pass down to lower levels. These are points 

 still to be investigated. 



No one, so far as I know, has previously called attention to the ex- 

 ceedingly large amount of fine degeneration which occurs amongst the 

 cells of the nuclei pontis following motor lesions with the exception 

 of Dejerine and Long [17] in an article published in 1898. This con- 

 tains a record of the examination of material from five cases of cere- 

 bral hemiplegia suitable for the Marchi method. They say: — "In the 

 grey substance of the pons the very fine and very numerous granules 

 which we have observed in two of the cases indicate a degeneration 

 of collateral and terminal fibres at this level, and this fact exi)lains 

 to us the atrophy of the grey substance of the pons which one sees 

 in old degenerations of the cms cerebri." Sherrington [lò\ (1890) 

 states that — "the islanded grey masses in the pons lying close to 

 the fibre bundles of the crustal tracts among the deep transverse 

 pontal fibres" in monkeys is one of "the regions of gi'ey matter in 

 which in- association with pyramidal degenei'ation, scattered fibres may 

 be found degenerated". This was before the Marchi method had come 

 into general use, and these fibres probably did not i'e])resent tcniiiual 

 degeneration. In all the animals I have examinent this (lue degene- 

 ration has been present, and often exceedingly abundant; it is strictly 

 confined to the side of the pons homolateral with the lesion. It is a 

 well known fact that atrophy of the nuclei puntis follows degene- 



