DISSECTION OF THE HEAD AND NECK 



359 



(1) Prefrontal section, passing through the front of the lobus frontalis 



about live centimetres in front of the sulcus centralis and parallel 

 to it. 



(2) Operculo frontal or pediculo frontal section, through the pars opercu- 



laris of the gyms frontalis inferior and the corresponding portions 

 of the gyrus frontalis medius and gyrus frontalis superior ; in other 

 words, through the " feet" of the frontal gyri. 



(3) Frontal section, through the middle of the gyrus centralis anterior. 



(4) First parietal section, through the middle of the gyrus centralis pos- 



terior. 



(5) Second parietal or pediculoparietal section, through the anterior ex- 



tremities ("feet") of the lobulus parietalis superior and lobulus 

 parietalis inferior. 



(6) Occipital section, about one centimetre in front of the fissura parieto- 



occipitalis. 



FIG. 170. 

 Operculofrontal 



Prefrontal section 



Frontal pj^ parietal 



Second parietal 



Occipital 



Prefrontal 



Operculofrontal 



Frontal / 



First parietal / 



Second parietal 



Pitres' method of sectioning the cerebral hemisphere. 1 



It will be advantageous to the student while studying anat- 

 omy to become familiar with these obliquely frontal sections, as 

 well as with the vertical frontal, for it is the former that are 

 more often employed at the autopsy table of the pathological 

 laboratories. 



The prefrontal section shows the cortex and white matter of the three 

 frontal gyri, the orbital gyri, and the medial surface of the frontal lobe. 



The pediculo frontal section passes through the three frontal gyri, anterior 

 end of island, orbital gyrus, corpus callosum, eaput nuclei caudati, ante- 

 rior part of nucleus lentiformis, and lentieulostriate part of capsula 

 interna. 



1 The lines indicating the planes of the sections slope too much in this figure. 



