GENERAL HISTOLOGY OF THE NERVOUS SYSTEM. 123 



be exposed, and small bits are to be torn out in a similar way. 

 They may be mounted in glycerine or dammar varnish. The 

 nerve-trunks can be readily seen ; they will contain, on an 

 average, from two to three fibres perhaps, and form a large- 

 ineshed plexus. The ganglionic enlargement may be found 

 where three or four bundles meet, or in the course of a single 

 bundle. The diameter of the enlargement is three to five times 

 the size of the bundle. 



AuerbacTi 1 s plexus, called after its discoverer, is seen by 

 taking the same specimen, and tearing out thin laminse from 

 the muscle, at the junction of their longitudinal and trans- 

 verse coats. The ganglionic bodies are nodular, and contain 

 numerous nuclei. It is said that they may be isolated by 

 immersion of the muscular tissue eight to ten days in a 10 per 

 cent, solution of common salt. Guinea-pigs furnish the best 

 specimens. 1 There are both coarse and fine networks. 



Termination of nerves. There are various methods which 

 have been described, and these are : 1, by undivided or free 

 endings (tendons, conjunctiva) ; 2, by end bulbs (cornea) ; 3, 

 by terminal loops ; 4, in corpuscles (seminal canals Letzerich) ; 

 5, by networks (peritoneum) ; or, finally, 6, in a special appa- 

 ratus (Pacinian pr Meissner's corpuscles). When nerves termi- 

 nate by networks, the meshes may be formed from the medul- 

 lated fibres, or those of Remak, and may consist of one or more 

 fine fibrils. They have been found in the skin, and are to be 

 seen in the submucous tissue of the intestines, in the cornea, 

 and elsewhere. Termination by bulbs has been closely investi- 

 gated by Krause. The bulbs are described as having a diam- 

 eter of ^ millimetre, and ovoid-shaped in man, with a thin 

 capsule of connective tissue. One or more fibres appear to 

 enter the bulb, and, penetrating some distance, end in a knob. 

 They have been found in the conjunctiva, in the mucous mem- 

 brane of the floor of the rnouth, lips, soft palate, and tongue, 

 and in the glans penis and clitoris. In the cavity of the mouth 

 they are placed in the papillae. The bodies Krause has 'ob- 

 served in the clitoris are somewhat peculiar ; they are variously 

 shaped, and have a mulberry-like surface. 



These corpuscles, about which there has been so much dis- 

 cussion, and which some excellent observers (Waldeyer, Arnold) 



1 Frey : Das Mikroskop. , Leipzig, 1877. 



