THE TACTILE CORPUSCLES OF MEISSNER 



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corpuscles cf Meissner, the tactile corpuscles of Krause, the tactile menisques, 

 and the corpuscles of Golgi. 



The Pacinian Corpuscles. These nerve endings, named after their 

 discoverer Pacini, are elongated oval bodies situated on some of the cerebro- 

 spinal and sympathetic nerves. They occur on the cutaneous nerves 

 of the hands and feet, the branches of the large sympathetic plexus about 

 the abdominal aorta, the nerves of the mesentery, and have been observed 

 also in the pancreas, lymphatic glands, and thyroid glands, figure 100. 

 Each corpuscle is attached by a narrow pedicle to the nerve on which it is 



FIG. 



FIG. ioi. 



FIG. 100. Pacinian Corpuscle of the Cat's Mesentery. The stalk consists of a nerve 

 fiber, n, with its thick outer sheath. The peripheral capsules of the Pacinian corpuscle are 

 continuous with the outer sheath of the stalk. The intermediary part becomes much 

 narrower near the entrance of the axis-cylinder into the clear central mass. A hook- 

 shaped termination with the end-bulb, a, is seen in the upper part. (Ranvier.) 



FIG. ioi. Summit of a Pacinian Corpuscle of the Human Finger, showing the 

 Endothelial Membranes Lining the Capsules. X 220. (Klein and Noble Smith.) 



situated, and is formed of several concentric layers of fine membrane, each 

 layer being lined by endothelium, figure ioi. A single nerve fiber passes 

 through its pedicle, traverses the several concentric layers, enters a central 

 cavity, and terminates in a knob-like enlargement or in a bifurcation. 



The physiological import of these bodies is still obscure. 



The Tactile Corpuscles of Meissner. They are found in the papillae 

 of the skin of the fingers and toes or among its epithelium. When simple 

 they are small, slightly flattened transparent bodies composed of nucleated 

 cells enclosed in a capsule. When compound, the capsule contains several 



