ABSORPTION FROM THE DIGESTIVE CAVITY. 



the middle of the villus. The vein returning the blood begins at the point 

 of the villus, and generally goes directly into the submucous tissues, without 

 receiving any lateral branches. No nervous elements have been traced into 

 the villi ; but a layer of muscular fibre-cells has been shown by Kolliker 

 and others to surround the lacteal tubes, the contraction of which has been 

 frequently observed whilst absorption is going on, and has an important in- 

 fluence on the propulsion of the fluids contained within those vessels. 



135. When the Villi are examined at such a period after a meal contain- 

 ing oleaginous matters as has sufficed for its partial digestion, their lacteals 

 are seen to be turgid with chyle, the extremity of each being imbedded in 

 a collection of globules presenting an opalescent appearance, and giving to 

 the end of the villus a somewhat mulberry-like form. It was supposed by 

 Prof. Goodsir, 1 by whom this appearance was first observed, that these glob- 

 ules were cells developed within the basement-membrane during the act of 

 absorption, from what he considered to be granular germs visible in the same 

 situation during the intervals of the process ; but there can now be little 

 doubt that the appearance in question is really due to the distension of the 



Perpendicular section through one of Fever's patches in the lower part of the ileum of the Sheep. 

 A, Lacteal vessels in the villi. L. The superficial layer of the lacteal vessels (rete augustum). D. The 

 deep layer of the lacteals (rete amplum). E. Efferent vessels, provided with valves, a. Lieberkiihn'* 

 glands, p. Peyer's glands. H. Circular muscular layer of the wall of the intestine, o. Longitudinal 

 muscular layer, s. Peritoneal layer. 



cylindrical epithelial cells investing the villi with the lacteal fluid. As it is 

 a matter of much interest to examine and explain the mode in which absorp- 

 tion in this, its first stage, is effected, the attention of many observers has 



1 Edin. New Phil. Journ., July, 1842, and Anatom. and Pathol. Observ., pp. 5-10. 



