ASSOCIATION FIBRES 



891 



extends from the anterior perforated substance and the subcallosal gyrus around the genu of the 

 corpus callosum, then, under cover of the gyrus cinguU and around the splenium, and thence 

 do'miward and forward in the hippocampal gyrus to the uncus. It is chiefly an aggregation of 

 fibres of short course — fibres which associate neighbouring portions of the cortical substance 



Fig. 701. — Photograph of "Torn Preparation" of Cerebral Hemisphere showing 

 SOME or the Association Fasciculi. (After R. B. Bean.) 



.Central sulcus 



Long fibrae^ 

 propriae 



Superior longitu- 

 dinal fasciculus '^ 



, Fibrae propriae 



"■* External capsule 



>.^ Uncinate fas- 

 ciculus 



Superior and inferior longitudinal fasciculi 

 and temporal pontile path 



External capsule, posterior part 



Fig. 702. — Schematic Representation of Certain op the Association Pathways of the 



Cerebral Hemisphere. 



Fibrae propriae 



Superior longitudinal ,'; 



fasciculus , ' \ 



Stria terminalis 



of thalamus 



Cingulum 



Uncinate fasciculus 



Inferior longitudinal fasciculus 



beneath which they course, and which, by continually overlapping each other, form the bundle. 

 (3) The uncinate fasciculus is a hook-shaped bundle which associates the uncus and anterior 

 portion of the temporal lobe with the olfactory bulb, parolfactory area and anterior perforated 

 substance and perhaps the frontal pole with the orbital gyri. Its shape is due to its having to 

 curve medialward around the stem of the lateral cerebral fissure. 



