SUPRARENAL CAPSULES. 



435 



found in the cells of the innermost portion of the middle 

 layer. 



The external layer is made up of irregularly arranged cor- 

 tical corpuscles. Nearly all the cells of this layer contain 

 pigment granules. The connective-tissue here forms a reti- 

 culum, with variously shaped meshes, which contain greater 

 or smaller heaps of cells. 



The medullary substance has a whitish-gray appearance, and 

 is of a more delicate consistency than the cortex. It consists 



Fio. 188. Vertical section throncrh the medullary subFtance of the suprarenal capsule of the Cow. 

 a, blood- vessels ; 6, trabecnlse of medullary cells. Strieker. 



of a network of connective tissue, which contains in its meshes 

 the medullary corpuscles. These are pale cells with spherical 

 nuclei and large nucleoli. They may assume various shapes. 

 In man they are generally of an irregularly stellate or polyg- 

 onal form. Their protoplasm is finely granular, and they con- 

 tain, as a rule, much less fat and pigment than the cortical 

 corpuscles. Kolliker finds that they resemble the nerve-cells 

 of the central nervous system, but he adds that they cannot 

 be regarded as such nerve-elements. The medullary cells 

 assume a yellow or brownish color when treated with chromate 

 of potash or chromic acid. Since the cortex corpuscles are 

 not thus colored, this peculiar! ty may serve to distinguish one 

 cellular variety from the other. 



The connective-tissue framework of the medulla is called its 



