1 88 THE CEREBRUM. 



within the line of Baillarger; the axone runs inward to the white 

 substance. The external large pyramids are found in nearly 

 all parts of the cortex. They are replaced by a layer of large 

 stellate cells in the receptive visual cortex along the calcarine 

 fissure. The line of Baillarger in the calcarine cortex is so thick 

 and dense that Gennari and, later,- Vicq d'Azyr described it from 

 its naked eye appearance (Fig. 60). In the motor and common 

 sensor) 7 area the line can scarcely be made out ; while in the supe- 

 rior parietal gyms there are two Baillargic lines, the deep line coin- 

 ciding in position with the internal large pyramids. There are 

 some peculiar Golgi cells among these pyramids, wiiose axones 

 run horizontally and give off collaterals that form pericellular 

 baskets around the pyramids (Johnston). They are associative 

 in function. 



5. The layer of stellate or polymorphous cells presents great 

 variation in different regions and is a valuable guide for cortical 

 localization. It is best marked in the calcarine area (Fig. 60) 

 where it and the fourth layer are associated with the greatly thick- 

 ened Baillargic line (Gennari), though elsewhere it is situated 

 in the radiary zone of fibers. It is well marked in the auditory 

 cortex. In the motor area it is hardly distinguishable, but it 

 appears suddenly at the bottom of the central sulcus and forms 

 a distinct feature in the common sensory region of the posterior 

 central gyrus (Fig. 59). The cell-bodies of the stellate layer 

 measure five to eight microns in diameter and are of many shapes, 

 some being pyramidal. They are richly branched." The dendrites 

 arborize at once near the cell-body. The axones of a considera- 

 ble number of cells extend horizontally within the layer, helping 

 to form the line of Baillarger; while others run toward the surface 

 and end in the overlying laminae. 



6. Internal Layer of Large Pyramids (Fig. 59). This is the 

 most important layer of the cortex for localization. It lies in the 

 radiary zone of fibers and is present in almost every part of the 

 cerebral cortex, though distinguished by definite variations in the 

 different regions (Figs. 59, 60 and 61). Its great pyramids are 

 intermingled with irregular cell-bodies of the Golgi type and 

 with Martinotti cells. The giant pyramids (Betz), or ganglionic 



