270 



THE ORGANS 



very thin or entirely absent. In the connective tissue, lying to the 

 outer side of the circular muscle coat, is the nerve plexus of Auerbach. 

 J^For details see page 276.) 



4. The serous coat consists, as in the stomach and small intestine, 

 of loose connective tissue covered by a single layer of mesothelium. 



The Vermiform Appendix 



*^"' The vermiform appendix is a diverticulum from the large intes- 

 tine. Its walls are continuous with those of the latter, and closely 











Oc>tl< 



il*^?' 







Fig. 1 74. — Transverse Section of Human Vermiform Appendix. (Technic 2, p. 275.) 

 a, Mesoappendix; &, serous membrane (serosa); c, outer longitudinal muscle layer; d, 

 inner circular muscle layer; e, submucosa;/, groups of fat cells in submucosa; g, blood- 

 vessels in submucosa; h, lymph nodules; i, stroma; j, glands opening into lumen and cut 

 in various planes; musculans mucosae not i)rcsent. 



resemble them in general structure. There are the same four coats, 

 mucous, submucous, muscular, and serous. 



I. The mucous membrane (Fig. 174) consists of epithelium, 

 glands, stroma, and muscularis mucosae. The epithelit^m resembles 



