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PHYSIOLOGY 



(3) Below the pyramidal layer we find a stratum of small cells, most of 

 which are stellate. in form. This is known as the stellate or granule layer, 

 or middle cell lamina. 



(4) Internal to the granule layer is the inner fibre lamina. In the 

 motor cortex and in certain other parts of the brain this contains large 

 solitary cells, which in the motor area receive the name of the cells of Betz. 



(5) Most internal of all, lying next to the white matter, is the poly- 



I 



FIG. 219. 



Schematic representation of the neuro-fibrillar apparatus of a cortical 

 pyramidal cell. (After CAJAL.) 

 a, axon ; dh, dendrites. 



morphous layer or inner cell lamina, composed of many types of cells, among 

 which spindle-shaped cells predominate. Other cells are also found resem- 

 bling pyramidal cells of the more superficial layer, but directed in the reverse 

 direction, so that their axons take a course towards the surface. These 

 are the cells of Martinotti. We also find Golgi cells with a freely branching 

 axon, which terminates in the adjacent grey matter. 



