374 



THE NERVOUS SYSTEM. 



spaces containing fluid ; through its pedicle passes a single 

 nerve-fibre, which, after traversing the several concentric 

 layers and their immediate spaces, enters a central cavity, and, 

 gradually losing its dark border, and becoming smaller, ter- 



Fio. 137. 



FIG. 136. 



FIG. 136. Extremities of a nerve of the finger with Pacinian corpuscles attached. 

 A. Nerve from the finger, natural size ; showing the Pacinian corpuscles. B. Ditto, 

 magnified two diameters, showing their different size and shape. 



FIG. 137. Pacinian corpuscles from the mesentery of a cat ; intended to show the 

 general construction of these bodies. The stalk and body, the outer and inner 

 system of capsules with the central cavity are seen. a. Arterial twig, ending in 

 capillaries, which form loops in some of the intercapsular spaces, and one penetrates 

 to the central capsule, b. The fibrous tissue of the stalk, prolonged from the neuri- 

 lemma. n. Nerve-tube advancing to the central capsule, there losing its white sub- 

 stance, and stretching along the axis to the opposite end, where it is fixed by a 

 tubercular enlargement. 



minates at or near the distal end of the cavity, in a knob-like 

 enlargement, or in a bifurcation. The enlargement commonly 

 found at the end of the fibre, is said bv Pacini to resemble a 



