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lecular and cellular contents of the glands are so abundantly 

 traversed by minute bloodvessels, important changes may mu- 

 tually take place between these contents and the blood in the 

 vessels, material being abstracted from the latter, elaborated 

 by the cells, and then restored to the blood, much in the same 

 manner as is believed to be the case in the so-called vascular 

 glands, such as the spleen, thymus, and others ; and that thus 

 Peyer's glands should also be regarded as closely analogous to 

 these vascular glands. Possibly they may combine the func- 

 tions both of lymphatic and vascular glands, absorbing and 

 elaborating material both from the chyle and from the blood 

 within their minute vessels, and transmitting part to the lac- 

 teal system and part direct to the blood. 



Brunrfs glands (Fig. 80) are confined to the duodenum; 

 they are most abundant and thickly set at the commencement 



FIG. 80. 



Enlarged view of one of Brunn's glands from the human duodenum (from Frey). 

 The main duct is seen superiorly ; its branches are elsewhere hidden by the bunches 

 of opaque glandular vesicles. 



of this portion of the intestine, diminishing gradually as the 

 duodenum advances. Situated beneath the mucous membrane, 

 and imbedded in thesubmucous tissue, they are minutely lobu- 

 lated bodies, visible to the naked eye, like detached small por- 

 tions of pancreas, and provided with permanent gland-ducts, 

 which pass through the mucous membrane and open on the 

 internal surface of the intestine. As in structure, so probably 

 in function, they resemble the pancreas; or at least stand to it 

 in a similar relation to that which the small labial and buccal 



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