CH. XLIV.] 



THE ARCHIPALLIUM AND NEOPALLIUM 



647 



and this is associated with smell, the most important sense in the 

 old primitive brain. The rest of the cortex is termed the neopallium 

 (or new cortex) ; it subserves the functions of hearing, vision, touch, 

 and the muscular sense, and is also concerned in the origination of 

 those volitions which result in movements initiated and guided by 

 those senses. The progressive development of the neopallium is 

 especially marked in the primates and in man, for in these the more 

 primitive olfactory and oral senses are unimportant in the struggle 

 for existence ; in man the receptive olfactory membrane in the nose 

 measures considerably less than a square inch instead of the many 

 square feet it extends over in the shark ; but the visual and other 

 faculties enumerated become preponderatingly important as associa- 

 tive memory develops and the brain becomes the organ of mind. 

 The structure of the neopallium is more elaborate than that of the 

 archipallium. 



The following table will make the relationship of these parts 

 clear : 



THE VERTEBRATE BRAIN 

 consists of 



The Pala-encephalon, 

 old primitive brain. 



The Neo-encephalon, or new brain. 

 This consists of the cerebral cor- 

 tex (with its efferent and afferent 

 fibres) and may be subdivided into 



a. The Archipallium^ or 

 old cortex. 



6. The Neopallium, or 

 new cortex. 



