560 



OF SECRETION. 



Fig. 174. 



Fig. 175. 



Mucous coat of small intestines as altered in 

 fever; the follicles of Lieberkiilm filled with 

 tenacious white secretions. (After Boehm.) 



One of the glandulse majores simplices, 

 viewed from above, and seen in section; 

 from the large intestine. (After Boehm.) 



176. 



part, situated around the bases of the villi : in the foetus and newly-born child, 

 they are so abundant as to be almost in contact ; but in the adult, the intervals 

 increase, so as to occupy more space than the apertures. The glandulae of 

 the small intestine have long been known under the name of the follicles of 

 Lieberklihn ; they become particularly evident when the mucous membrane 

 is inflamed, being then filled with an opaque whitish secretion, which is absent 

 in the healthy state. Besides the foregoing descriptions of solitary glandulae, 

 the Cfficum and the lower part of the Rectum contain a number of simple and 

 large follicles, which produce slight rounded elevations on the surface of the 

 mucous membrane ; the centre of each of these elevations is perforated by an 

 aperture of the follicle; and around this are seen the orifices of the tubular 

 cosca, which closely envelop the globular follicle. These seem most abun- 

 dant where the largest quantity of mucus is required. They have been con- 

 founded with the glands of Brunner ; but are rather analogous to the solitary 

 Peyerian glands presently to be noticed. 



706. The true glands of Brunner are chiefly situated in the Duodenum ; 



and they lie not in the mucous but in the sub-mucous 

 tissue, where they form a continuous layer of white 

 bodies surrounding the whole intestine. Their size, 

 unless diseased, is scarcely that of a hemp-seed ; each 

 consists of numerous minute lobules, of which the 

 ducts open into a common excretory tube ; and in the 

 lobules may be distinguished the minute ramifications 

 of these ducts, with clusters of follicles forming acini, 

 of which about six hundred are computed to exist in 

 each. Hence these glands are of complex structure, 

 much resembling that of the Salivary glands and Pan- 

 creas, and entirely differing from all the other glan- 

 dulse of the walls of the alimentary canal. Of the 

 peculiar nature of their secretion nothing is known. 



707. The so-called Peyerian glands constitute, when aggregated together, 

 large patches on the mucous membrane of the small intestine, where they are 

 known as the glandule agminatas ; and it is to these alone that Peyer's name 

 is usually applied. Similar bodies, however, known as the glandulse solitarise, 

 exist separately in the lower part of the small intestines ; where they have 

 been confounded with the glands of Brunner, which do not extend beyond the 

 commencement of the Jejunum. The glands of Peyer, when examined in a 

 healthy mucous membrane, present the appearance of circular white slightly- 

 raised spots, about a line in diameter, over which the membrane is usually 

 less set with villi, and very often entirely free from them. Each of these 

 white spots, of which a large number are contained in the agminated glands, 



Conglomerate gland of Brun- 

 ner, from commencement of 

 duodenum ; magnified an hun- 

 dred limes. (After Boehm.) 



