OF DENISON UNIVERSITY 
47 
able that the groups of ganglion cells, from which the cranial nerves 
arise, and which have been made known by Stilling as the nuclei of 
sensory roots, consist of cells in form entirely similar to those from the 
anterior and posterior cornua of the spinal marrow, and that they, like 
these, send off only one axis cylinder, which passes toward the per- 
piphery, while the other processes divide into innumerable primitive 
fibrils.”* 
Turning to the morphological aspects of the same problem, the 
results are similar. Thus in the literature before 1870, although all 
agreed that the cortex is laminated, Baillarger (1840), Gerlach (1852), 
Berlin (1859), and others, described six layers, Koelliker, four to six, 
Arndt, five to six, and Meynert, nine. The giant pyramids or 
“pyramidal bodies,” {Meynert), were described by Arndt as pyra- 
mids with five or more fine branches from the base, which divide 
dichotomoLisly and are lost in a nervous reticulum of the ground 
substance, while the apex process passes upward, then abruptly turns 
downward to form an axis cylinder. Meynert, and after him Loech- 
ner, Kollman and Stieda, on the contrary, claim that the apical pro- 
cess divides, while, besides the baso-lateral processes there is a me- 
dian basal double-contoured fibre which passes into an axis cylinder. 
Meynert say, (Psychiatry, p. 70): “Betz has stated that the ante- 
rior central convolution contained groups of particularly large pyra- 
mids, which he thought were the circumscribed motor centres which 
Hitzig, on the strength of his physiological experiments, relegated ex- 
clusively to the anterior central convolution of the brain of dogs and 
monkeys. Apart from the mistake which Hitzig made in establishing 
the homologue in carnivora of the anterior central convolution, it has 
been proved that the size of the pyramids depends upon their distance 
from the cortical surface. The largest pyramids will, therefore, be 
found in the broadest cortical region ; but the broadest cortical region 
is that of both central convolutions. * * * The largest pyramids 
appear to be arranged in small groups at some distance from one an- 
other. It would be wrong to argue from this that these large pyramids 
have a different signification from the smaller ones. Luys is in a great 
measure responsible for this mistake. Betz appears to me not to have 
Raue, Psychology as a Natural Science applied to the Solution of Occult 
Psychic Phenomena, 1889.] 
i 
