302 



DIGESTION. 



is surrounded by openings like those of Lieberkiihn's 

 follicles (see fig. 77) except that they are more elongated ; 

 and the direction of the long diameter of each opening is 

 such that the whole produce a radiated appearance around 

 the white sacculus. These openings appear to belong to 

 tubules identical with Lieberkiihn's follicles : they have no 

 communication with the sacculus, and none of its contents 

 escape through them on pressure. Neither can any \ 



Fig. 77. t 



Fig. 76.= 



permanent opening be detected in the sacculus or Peyer's 

 gland itself (see fig. 78). 



Each gland is an imperfectly closed sac or follicle formed 

 of a tolerably firm membranous capsule of fine connective 

 tissue, imbedded in a rich plexus of minute blood-vessels, 

 many fine branches from which pass through the capsule 

 and enter, chiefly loopwise, the interior of the follicle 

 (fig. 79). Entering into the formation of the sacculus, 



* Fig. 76. Solitary gland of small intestine (after Boelim). 



t Fig. 77. Part of a patch of the so-called Peyer's glands magnified, 

 showing the various forms of the sacculi, with their zone of foramina. 

 The rest of the membrane marked with Lieberkiihn's follicles, and 

 sprinkled with villi (after Boehm). 



