STRUCTURE OF THE LOBES OF THE CEREBRUM. 389 



tions, as the result of a colour-contrast, are surrounded by a 

 bluish-green halo. 



Berlin has already noticed that granules and fusiform bodies 

 occur in the cortex of the cerebrum. I have shown that these 

 forms, intermingled with a few larger pyramidal cells, give 

 their peculiar characters to the fourth and fifth layers of the 

 cortex of the cerebrum. The elements of the fourth layer 

 (fig. 235, 6) are of irregular form, from 8 to 10 jit in diameter, 

 rarely triangular or elongated in a direction parallel to the 

 radial fasciculi. They are more closely arranged than in the 

 adjoining third and fourth layers. 



They remind one of the nerve corpuscles that are found in the 

 internal granule-layer of the retina, and in the gelatinous nucleus of 

 origin of the large root of the fifth pair of nerves. 



The peculiar elements of the fifth layer, the spindle-shaped 

 bodies 30 p in length (fig. 235, d), are found least intermingled 

 with others in the internal half of this layer, and are more 

 scattered from this point into the medullary laminae (m). At 

 the summit of the transverse section of a convolution these 

 fusiform bodies are vertically placed, and are parallel to the 

 pyramids; but in the groove between two convolutions they lie 

 horizontally (fig. 234, 5), and the pyramids stand vertically 

 upon them. And just as the pyramids are in a line with the 

 projection system of fasciculi, so the fusiform bodies of the 

 fifth layer correspond in direction with the fibrse arcuatae, 

 which on the one hand decussate in the furrow between two 

 convolutions with the projection fasciculi, whilst, on the other 

 hand, in the summit of the convolution they run parallel with 

 these fasciculi. 



These fusiform cells may therefore be regarded as intercalated 

 cells of the connecting system (Associationssystem). They 

 may be designated the claustral formation (Vormauer-for- 

 mation), because, as will be presently shown, the claustrum 

 represents only a compact accumulation of cells of the inner- 

 most layer of the cortex. 



They cannot however, merely on account of their fusiform 

 shape, be considered as bipolar cells, since they also apparently 



