204 EDWARD HORNE CRAIGIE 
Brodmann (loc. cit.) considers Kappers’ theory groundless, 
describing it as a wild hypothesis which is quite untenable and 
erroneous. Van Valkenburg (’13, 713 a[?]), however, has brought 
forward certain evidence which seems to support Kappers’ view; 
as have also Nissl, Nieuwenhuijse, and Bielschowsky, whose 
contributions are summarized by Van’t Hoog (’20). The last- 
mentioned author also adduces further evidence in favor of 
the theory of Kappers, and stresses particularly the rdle of 
the cells in the lamina granularis interna. These he considers, 
emphasizing a point concerning which Kappers had been less 
positive, to be ‘matrix cells,’ i.e., cells which have retained much 
of their primitive character and potentialities, which are still 
capable of a wide range of differentiation, and from which the 
other layers have probably been derived phylogenetically. It 
may be pointed out that, in the ontogeny of the cerebral cortex 
of the rat, this layer is the last one to become distinguishable 
according to Sugita (’17), but, on the other hand, it is said by 
Tandler and Kantor (’07) to be the first to appear in the embryo- 
logical development of the reptilian cortex. Thus practically all 
the available evidence, whether it be conclusive or not, seems to 
point in the direction outlined by Kappers. 
It would be an interesting observation if it was really the 
more recent and more highly specialized portions of the cortex 
which were the less richly vascular, and we have possibly a 
somewhat similar case among the lower centers studied. Refer- 
ence to table 3 will show that the chief vestibular nucleus is 
more highly vascular than the cerebellar cortex, the dentate 
nucleus, or Deiters’ nucleus. Now the cerebellar gray matter 
is a highly specialized derivative of the primitive acoustico- 
lateral area, from which, of course, both the other nuclei are 
also developed. Moreover, the chief vestibular nucleus is com- 
posed of small, granule-like cells, most of the axones of which 
are said to take up a longitudinal direction in the substantia 
reticularis, so that it seems not unreasonable to suppose that 
it may be less highly differentiated than either the nucleus of 
Deiters or the cerebellum. This, however, is pure speculation 
without definite authority or conclusive basis. 
