1061 



Herbst has described a nerve-ending somewhat similar to the Pacinian corpuscle, in the mucous 

 membrane of the tongue of the duck, and in some other situations. It differs, however, from 

 the Pacinian corpuscle, in being smaller, in its capsules being more closely approximated, and 

 especially in the act that the axis-cylinder in the central clear space is coated with a continuous 

 row of nuclei. These bodies are known as the corpuscles of Herbst. 



The corpuscles of Golgi and Mazzoni are found in the subcutaneous tissue of the pulp of 

 the fingers. They differ from Pacinian corpuscles in that their capsules are thinner, their con- 

 tained cores thicker, and in the latter the axis-cylinders ramify more extensively and end in 

 flat expansions. 



The tactile corpuscles of Wagner and Meissner (Fig. 936) are oval-shaped bodies. Each 

 is enveloped by a connective-tissue capsule, and imperfect membranous septa derived from this 

 penetrate the interior. The axis-cylinder passes through the capsule, and after making several 

 spiral turns around the body of the corpuscle ends in small globular or pyriform enlargements. 

 Thess tactile corpuscles occur in the papillae of the corium of the hand and foot, the front of 

 the forearm, the skin of the lips, the mucous membrane of the tip of the tongue, the palpebral 

 conjunctiva, and the skin of the mammary papilla. 



Terminal ramifications 

 of axis cylinders 



Nerve fibers 

 \ 



Connective tissue sheath 



FIG. 937. Nerve ending of Ruffini. (After A. Ruffini.) 



Corpuscles of Ruffini. Ruffini described a special variety of nerve-ending in the subcuta- 

 neous tissue of the human finger (Fig. 937); they are principally situated at the junction of the 

 corium with the subcutaneous tissue. They are oval in shape, and consist of strong connective- 

 tissue sheaths, inside which the nerve fibers divide into numerous branches, which show vari- 

 cosities and end in small free knobs. 



The neuro tendinous spindles (organs of Golgi) are chiefly found near the junctions of tendons 

 and muscles. Each is enclosed in a capsule which contains a number of enlarged tendon fasciculi 

 (intrafusal fasciculi). One or more nerve fibers perforate the side of the capsule and lose their 

 medullary sheaths; the axis-cylinders subdivide and end between the tendon fibers in irregular 

 disks or varicosities (Fig. 938). 



Tendon 

 bundles 



Organ of Golgi, showing 

 ramification of nerve-fibrils 



Muscular fibers 



FIG. 938. Organ of Golgi (neurotendinous spindle) from the human tendo calcaneus. (After Ciaccio.) 



The neuromuscular spindles are present in the majority of voluntary muscles, and consist 

 of small bundles of peculiar muscular fibers (intrafusal fibers), embryonic in type, invested by 

 capsules, within which nerve fibers, experimentally shown to be sensory in origin, terminate. 

 These neuromuscular spindles vary in length from 0.8 mm. to 5 mm., and have a distinctly 

 fusiform appearance. The large medullated nerve fibers passing to the end-organ are from 



