THE CEREBRUM 



433 



of the fornix to the under surface of the corpus callosum, 

 behind the posterior end of the septum pellucidum. On the 

 lateral side it is closed by the meeting of the roof and the 

 floor of the cavity. 



In the floor are several important objects which have 

 already been referred to. Latero-medially, and, at the same 

 time, to some extent from before backwards, they are (i) the 

 caudate nucleus ; (2) a groove extending obliquely, backwards 



Corpus callosum Chorioid plexus 



Lateral ventricle I [ Striae on corpus callosum 



Caudate nucleus I ! j Longitudinal fissure 

 Fronto-occipital fasciculus i l\ \ Septum pellucidum 



Vena terminal 



Subthalamic body I 



Thalamus 



3rd ventricle 

 Chorioid plexus 

 Red nucleus 



FIG. 168. Frontal section showing immediate relations of Lateral and 

 Third Ventricles. (Part of Fig. 188 enlarged.) 



and laterally, between the caudate nucleus and the thalamus, in 

 which are placed the vena terminalis (O.T. vein of corpus 

 striatum) and a white band called the stria terminalis (O.T. 

 tsenia semicircularis) ; (3) a portion of the upper surface 

 of the thalamus ; (4) the chorioid plexus ; (5) the thin, sharp 

 edge of the fornix. 



The caudate nucleus lies in the lateral part of the floor of 

 the central part of the lateral ventricle, and it narrows very 

 rapidly as it passes backwards. 



The vena terminalis is seen through the ependyma in the 

 groove between the caudate nucleus and the thalamus. It 

 joins the internal cerebral vein (O.T. vein of Galen) at the 

 interventricular foramen. In the same groove is placed the 

 stria terminalis a narrow band of white matter, which bends 



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