INTESTINAL NERVOUS PLEXUSES. 



851 



in ganglion-cells, which is situated between the circular and longitudinal muscular 

 fibres of the intestine, and to which he has therefore given the name of "plexus 

 myentericus." For the other observation we are indebted to Meissner, who has dis- 



Fig. 597 A. 



Fig. 597 B. 



Fig. 597 A. NERVOUS PLEXUS OP AUERBACH, FROM THE MUSCULAR COAT OP A 

 CHILD'S INTESTINE (from Kolliker). -^ 



The drawing represents three perforated ganglionic masses united by several nervous 

 cords, of which the thickest is also perforated, forming the "plexus myenteiicus." 



Fig. 597 B. SMALL PORTION OF MEISSNER'S SUBMUCOUS NERVOUS PLEXUS FROM THE 

 INTESTINE OP A CHILD (from Kolliker). ^- 



Two ganglia are represented, of which the cells are seen spreading into the nerve-twigs 

 connected with the ganglia : the fusiform particles in the nerve-twigs are small connective 

 tissue corpuscles. 



covered a second richly gangliated plexus of nerves situated in the submucous layer, 

 and which is found to communicate freely with the plexus myentericus of Auerbach 

 by means of the larger branches. Both plexuses extend through the whole length of 

 the intestine, from the pylorus to the anus. (Kolliker, Op. cit., pp. 430 and 432.) 



THE LARGE INTESTINE. 



The large intestine extends from the termination of the ileum to the anus. 

 It is divided into the csecum (including the vermiform appendix), the colon, 

 and the rectum ; and the colon is again subdivided, according to its direction, 

 into four parts, called the ascending, transverse, and descending colon, and 

 the sigmoid flexure. 



The length of the large intestine is usually about five or six feet ; being 

 about one-fifth of the whole length of the intestinal canal. Its diameter, 



3 K 2 



