THE INTESTINAL CAXAL. 



1025 



the salivary glands of the mouth, which are more compact. They are probably 

 direct continuations and higher specializations of the pyloric glands. They are 

 situated in the submucosa or in part in the mucous membrane. Their ducts 

 penetrate the muscularis inucosae, pass between the glands of Lieberkiihn and 

 open upon the inner surface of the intestine, or in some cases into the bases of 

 the crypts. 



The solitary glands (Fig. 645) are found scattered throughout the mucous 

 membrane of the small intestine, but are most numerous in the lower part of the 

 ileum. They are small, round, whitish and slightly prominent bodies 6 mm. to 

 3 mm. in diameter. They are formed on the mesenteric as well as free border, 

 between and upon the valvulae conniventes. The free surface of the follicle may 

 have villi upon it, but at the centre or cupola they are lacking. Each gland is 

 surrounded irregularly by the openings of the glands of Lieberkiihn. These so- 

 called glands have a structure similar to that of a lymph-node, consisting of 

 dense retiform tissue closely packed with lymph-corpuscles, and permeated by fine 

 capillaries. They have no ducts. The interspaces of the retiform tissue are con- 

 tinuous with larger lymph-spaces at the base of the gland by which they commu- 

 nicate with the lacteal system, or they may even hang into a lacteal sinus which 

 may nearly surround the nodule. The base of the nodule is in the subumcous 

 tissue. They penetrate the muscularis mucosse and enter the mucous membrane, 

 where they form slight projections of its epithelial layer. 



Agminated glands or Peyers glands (1677) may be regarded as aggregations 

 of the solitary glands, forming circular or oval patches (Fig. 646). They number 

 from twenty to thirty, and vary in length from one-half to four inches ; in width 

 from one and a half to two inches. They are largest and most numerous in the 

 lower two-thirds of the ileum. In the lower part of the jejunum they are small 



FIG. 645. Section of a solitary gland of the small intestine. 

 .t.i n. Solitary gland, which has become partly broken 

 away. 6. Epithelium of cupola, c, c. Villi. d. Crypt of Lieber- 

 kuhh. e, e. Muscularis mucosae. /. Submucous coat. 



FIG. 646. Patch of Fever's glands from 

 the ilenm, slightly magnified. (Boehm.) 



and few and of a circular form. They are occasionally seen in the lower duode- 

 num. They are placed lengthwise to the intestine, covering that portion of the 

 tube opposite the attachment of the mesentery, hence to see them well open the 

 bowel along its mesenteric attachment. 



Each patch is formed of a group of lymph-nodes which are similar to the sol- 

 itary glands above described. Each follicle becomes somewhat pyramidal, due to 

 pressure, and they lose much of their individuality, being most distinct along the 



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