524 'Journal of Comparative Neurology and Psychology. 



extensive fonnation which in primitive forms has essentially the 

 same structure and connections in all of its parts. This statement of 

 fact is subject to revision if further studies show it to be incorrect. 

 With regard to the name, however, I find that the extension of the 

 term epistriatum to include all of this formation has led to miscon- 

 ceptions of my meaning. This formation may be described as the. 

 visceral correlating center of the telencephalon, or as the correlating 

 substance of the visceral sensory zone of the telencephalon. Instead 

 of the term primitive epistriatum used above, this might be called 

 the primitive visceral cortex. The dorsal portion of it becomes the 

 true visceral cortex (archipallium) when it receives tertiary olfactory 

 and gustatory fibers. 



Some of the factors which enter into the definition of the term 

 cortex cerebri may be indicated as follows : 



a. The term is applied only to structures in the telencephalon 

 (excludes lobi inferiores, etc.) ; 



h. The afterent paths of the cortex are predominantly of the third 

 order (excludes the secondary olfactory centers; the cortex shows an 

 uncertain grade of development in the more primitive forais) ; 



c. The cortex serves functions of correlation for afferent impulses 

 of tw^o or more kinds (olfactory, gustatory, optic, auditory, etc. ; 

 excludes the epistriatum sensu stricto or nucleus amygdulse) ; 



Whether such correlating centers are superficial in position is 

 not of essential importance. The general cortex of mammals is 

 separated from the ventricle only by fibers related to the cortex itself, 

 i. e., by its own white matter. The question of superficial position 

 is of much less importance in the case of the cerebral cortex than in 

 that of the inferior olives, the medial and lateral geniculate bodies, 

 and other centers which are separated from the ventricle by 

 voluminous fiber bundles and gray masses which have no direct rela- 

 tion to themselves. 



The point of view of the writer stands in contrast to that of Kappers 

 who in his recent paper (1909) extends the concept of cortex to the 

 lobus olfactorius (^'paleocortex") although the centers concerned are 

 simple secondary olfactory centers throughout the vertebrate series. 

 His reason for this is that these centers occupy a superficial position 



