INTESTINAL CANAL. 31 



An abundance of Mucous Glands is found deposited in the 

 cellular coat of the small intestine, between the muscular and 

 the villous; their ducts open upon the internal surface of the 

 latter, in the interstices of the villi, and from their sm<(llness 

 require the intestine to be floated in water, and examined with 

 a magnifying glass, before they can be recognised. In order 

 to see the glands themselves, the intestine must be cleaned by 

 soaking it in water; it is then to be slit open longitudinally, and 

 held between the eye and the light, in which case the glands 

 appear like little points or spots in the thickness of the intestine. 

 They are more abundant in the beginning of the latter, decrease 

 about its middle, and increase again towards its termination. 

 Their structure is very simple, as they consist in a congeries 

 of blood vessels, terminating in short canals secreting mucus.* 



Some of these glands are microscopical, and are called cryptae; 

 others are to be found from that size to a line in diameter, and 

 flattened. They are either alone or in clusters. The former 

 (GlandulcB Solitaries, Brunneri,) are found principally about the 

 duodenum and the neighbouring portion of the small intestine, 

 but also exist all the way down in a scattered manner. The lat- 

 ter (Glandules Jlgminatce, Peyeri,) exist principally in the lower 

 part of the small intestine, and are collected into clusters var} 7 - 

 ing from a few lines to three or four inches in length, but seldom 

 more than from eight to twelve lines broad. They are, for the 

 most part, in elliptical patches, which, in a healthy state, may be 

 recognised rather by a slight, discoloration, than by the more or- 

 dinary means, and are generally situated some distance from the 

 mesentery. There are about thirty of these clusters, of all sizes, 

 in the ileum, and they are placed nearer and nearer to one another, 

 in approaching the ileo-colic junction. All of these muciparous 

 glands are too much flattened to project sensibly into the cavity 

 of the intestine, and, when they do, there is reason to believe that 

 they are in a diseased state, at least in the adult. For the most 

 part, in children, the glands of Brunner may be seen in the whole 

 length of the small intestine. 



The mucous coat of the small intestine is every where ex- 

 tremely vascular. 



* Soemmering, de Corp. Hum. Fabrica. 



