ORGANS OF THE BODY. 



475 



Fig. 455. Vertical section of the 

 human gastric mucous membrane, 

 a, ridges ; 6, peptic glands. 



mucous membrane, and the reticular lymphoid substance of the mucosa 

 of the small intestine. 



The almost innumerable glands of the stomach are of two kinds, not 

 always easy to distinguish from one another, 

 however. These are the peptic and gastric 

 mucous glands. 



The first of these are those blind tubules, 

 already mentioned in section 198, which are 

 closely crowded together, and occupy the 

 whole thickness of the gastric mucous mem- 

 brane in vast numbers (fig. 455, b). The 

 fact that in the neighbourhood of the pylorus 

 in the rabbit about 1894 may be counted 

 upon 1 Q mm. of surface, will give some 

 idea of their abundance. Their length, which 

 corresponds to the depth of the mucosa, is on 

 an average about 1'13 mm., but may fall to 

 the half of this, as well as exceed it by more 

 than double. Their transverse diameter ranges 

 from 0-0564 to 0'0451 mm. In children the 

 tube is shorter and of smaller calibre. 



The openings of these tubuli, which may be either grouped together 

 or parted by regular intervals from one another, are roundish orifices 

 considerably decreased in size by the columnar epithelium cells with 

 which they are lined, and which are arranged in a radiating manner 

 (fig. 456). 



Both chemically and mechanically there may be easily demonstrated a 

 membrana propria on all the tubuli, formed by 

 a condensation of the soft loose connective- 

 tissue of the mucosa in which flat stellate cells 

 have been met with. In the human subject 

 this is only slightly wavy in outline (fig. 457), 

 but in many animals it is on the contrary 

 markedly sacculated, as, for instance, in the 

 dog. The blind end of the tube, which is usually 

 more or less bulbous, is that at which it attains 

 its greatest calibre, while towards its opening it 

 is generally somewhat contracted. Double 

 tubuli, although of rare occurrence, may fre- 

 quently be simulated by the crossing of the 

 extremities of adjacent tubuli. Treatment with alkali will generally, 

 however, bring out the true arrangement of parts. 



Only on very limited portions of the human stomach are deviations 

 from the arrangement of the peptic cells just described to be met with. 

 Thus a very narrow band of compound tubules is to be found around the 

 cardiac extremity, of which fig. 460, 1, taken from the same region of the 

 dog's stomach, will give an idea. From a common excretory duct of 

 greater or less length (a) 4, 5, 6, or 7 gland tubules spring. 



Such compound peptic follicles appear to exist in much greater abund- 

 ance among the mammalia. 



As regards the contents of these peptic glands the earlier views 

 may be summed up as follows. Columnar epithelium lines the depres- 

 sions to a greater or less distance (fig. 460, b). Intermediate cellular 



Fig. 456. Surface of the stom- 

 achal mucous membrane, with 

 scattered openings of the 

 peptic glands, showing also 

 the cylinder epithelium lining 

 the latter. 



