532 



DIGESTION. 



Fi 238 



however, more numerous in the jejunum than in the duodenum ; and, 

 in the course of the ileum, they gradually disappear, and are replaced 

 by simple longitudinal rugae. The villi, too, which are chiefly destined 

 for chylous absorption, abound in the jejunum, but gradually disappear 

 in the ilerim. The mucous membrane of both is largely supplied with 

 follicles, called glands of Peyer, Btfcmer, and Lieberkiihn ; some, if 

 not all, of which are probably -concerned in secreting the succus enteri- 

 cuSj succus intestinalis, a mucous fluid, to which in digestion Haller 

 attached unnecessary importance. M. Lelut 1 estimates the number of 

 these glands in the small intestine at 40,000. Dr. Horner considers 

 the follicles to be formed, in every instance, of meshes of veins ; the 

 arteries entering inconsiderably into their composition, in about the 

 same proportion as they do in other erectile tissues. 2 



The glands, as they are termed, of the small intestine have long been 

 known under the name of follicles of Lieberkiihn. These become 

 especially evident if the mucous membrane is 1 'in- 

 flamed, when they are filled with an opaque whitish 

 secretion, which is absent in the healthy state. 3 



The true glands of Brunn or Brunner are 

 chiefly in the duodenum. They are situate in the 

 submucous tissue, where they form a continuous 

 layer of white bodies surrounding the intestine. 

 They are not larger than a hemp-seed ; each con- 

 Hiied with tenacious sisting of numerous minute lobules, the ducts of 



ve!- lte (Boehm 1 ) "* Fe ~ wn ^ c ^ P en ^ nto a common excretory duct. They 

 are complex structures, differing from the other 

 glands and follicles of the intestines. Nothing is positively known of 

 the nature of their secretion. 



The glands of Peyer form large patches on the mucous membrane, 

 when they are called glandule agminatse and 

 Peyer 's patches. Examined in a healthy mucous 

 membrane, they have the appearance of circular 

 white, slightly raised spots, about a line in dia- 

 meter, over which the mucous membrane is least 

 studded with villi, and often wholly without them. 

 On rupturing one of the white bodies a cavity is 

 found, but it has no excretory duct. It contains 

 100" a grayish-white mucous matter. There are like- 

 wise closed solitary glands in both the small and 

 large intestines. 4 The precise use of the glands 

 of Peyer is unknown. Wagner 5 has well observed, that the intimate 

 structure of the whole of these glandular bodies requires farther study, 

 and is almost as little known as their individual functions. There is 

 reason to believe, however, that they secrete a putrescent matter from the 

 blood, which may be concerned in giving to the excrement its peculiar 

 odour; this matter, as in other cases, being formed by cells, which 



1 Gazette Medicale, Juin, 1832. 



2 Op. cit., h. 54. 3 Boehm, cited in Brit, and For. Med. Rev., i. 521, Lond., 1836. 

 4 Baly, Lond. Med. Gazette, Mar., 1847. 



* Elements of Physiology, translated by R. Willis, 137, Lond., 1812. 



Fig. 239. 



times. (Boehm.) 



