158 



ELEMENTS OF HISTOLOGY. [Chap. XVIIL 



matter (neuroglia and nerve ground network), with 

 few and small ganglion cells. 

 (2) A layer of small more or 

 less pyramidal ganglion cells 

 densely aggregated. (3) The 

 formation of the cornu Am- 

 monis. This is the principal 

 or broadest stratum of the 

 cortex ; it is composed of 

 several layers of large, pyra- 

 midal ganglion cells, increas- 

 ing in size as a deeper layer 

 is reached. 



The pyramidal cells of 

 this third and of the previous 

 second stratum consist of a 

 pyramidal body including an 

 oval vesicular nucleus (Fig. 

 93). From the body pass out 

 the following principal pro- 

 cesses : (a) the process of the 



apex, 



directed towards the 



Fig. 93. A large Pyramidal Ganglion 

 Cell of the Grey Cortex of the Human 

 Cerebrum. 



The process of theapex and the other processes 

 branch and break up into the fine nerve net- 

 work. The median process of the base of the 

 pyramid remains unbranohcd, and becomes 

 an axis cylinder of a nerve-fibre. (Atlas.) 



surface of the convolution ; 

 it can be traced for 

 a longer or shorter 

 distance. (6) The 

 lateral basilar pro- 

 cesses, and finally 

 the median basilar 

 process. This latter 

 is fine, remains un- 

 branched, and is an 

 axis cylinder process, 

 i.e., becoming in- 

 vested with a medul- 

 lary sheath is a nerve- 

 fibre of the central 



