INFLUENCE OF THE NERVOUS SYSTEM. 30 1 



correct, the absorbing surface is thereby greatly diminished. Zuwarykin and 

 Schafer suggest that the leucocytes, which have been observed between the columnar 

 cells of the villi of the small intestine, are carriers of at least part of the fat from 

 the lumen of the gut to the lacteal ; they also, perhaps, alter it for further use in the 

 economy. According to Zuwarykin, Peyer's patches in the rabbit seem to be 

 especially active in the absorption of fat, so that he attaches great importance to 

 the leucocytes of the adenoid tissue in the absorption of fat.] 



[According to Griinhagen there are several channels for the absorption of fats, but they are 

 different in different animals. Some are absorbed by the columnar epithelium cells themselves, 

 and some passes between them.] 



The activity of the cells of the intestine with pseudopodial processes may be studied in the 

 intestinal canal of Distomum hepaticum. Sommer has figured these pseudopodial processes 

 actively engaged in the absorption of particles from the intestine. 



193. INFLUENCE OF THE NERVOUS SYSTEM. With regard to the 

 influence of the nervous system upon intestinal absorption, we know very little. 

 After extirpation of the semi-lunar ganglion, as well as after section of the mesen- 

 teric nerves (Moreau), the intestinal contents become more fluid, and are increased 

 in amount ( 183). This may be partly due to diminished absorption. V. Than- 

 hoffer states that he observed the protrusion of threads from the epithelial cells of 

 the small intestine only after the spinal cord, or the dorsal nerves, had been divided 

 for some time. 



194. " NUTEIENT ENEMATA." In cases where food cannot be taken by the mouth, e.g., 

 in stricture of the oesophagus, continued vomiting, &c, food is given per rectum. As the diges- 

 tive activity of the large intestine is very slight, fluid food ought to be given in a condition 

 ready to be absorbed, and this is best done by introducing it into the rectum through a tube 

 with a funnel attached, and allowing the food to pass in slowly by its own weight. The patient 

 must endeavour to retain the enema as long as possible. When the fluid is slowly and gradu- 

 ally introduced, it may pass above the ileo-csecal valve. 



Solutions of grape-sugar, and perhaps a small amount of soap solution, are useful ; and 

 amongst nitrogenous substances the commercial flesh-, bread-, or milk-peptones of Sanders-Ezn, 

 Adamkiewicz, in Germany, and Darby's fluid meat, and Carnrick's beef-peptonoids in this 

 country, are to be recommended. The amount of peptone required is l'llgrm. per kilo, of 

 body-weight (Catillon) ; less useful are butter-milk, egg-albumin with common salt. Leube 

 uses a mixture of 150 grms. flesh, with 50 grms. pancreas and 100 grms. water, which he 

 slowly injects into the rectum, where the proteids are peptonised and absorbed. [Peptonised 

 food prepared after the method of Roberts is very useful ( 172).] The method of nutrient 

 enemata only permits imperfect nutrition, and at most only \ of the proteids necessary for 

 maintaining the metabolism of the body is absorbed (v. Voit, Bauer). 



195. CHYLE-VESSELS AND LYMPHATICS. Lymphatics. Within the tissues of the 

 body, and even in those tissues which do not contain blood-vessels, e.g., the cornea, or in those 

 which contain few blood-vessels, there exists a system of vessels or channels which contain the 

 juices of the tissues, and within these vessels the .fluid always moves in a centripetal direction. 

 These canals arise within the tissues in a variety of ways, and unite in their course to form 

 delicate and afterwards thicker tubes, which ultimately terminate in two large trunks which 

 open at the junction of the jugular and subclavian veins ; that on the left side is the thoracic 

 duct, and that on the right, the right lymphatic trunk. 



With regard to the lymph and its movements in different organs, it is to be noticed 

 that this occurs in different ways in different places. (1) In many tissues, the lymph- 

 atics represent the nutrient channels, by which the fluid that transudes through the 

 neighbouring vessels is distributed, as in the cornea and in many connective-tissues. 

 (2) In many tissues, as in glands, e.g., the salivary glands and the testis, the lymph- 

 spaces are the chief reservoirs for fluid, from which the cells during the act of 

 secretion derive the fluid necessary for that process. (3) The lymphatics have the 

 general function of collecting the fluid which saturates the tissues, and carrying it 

 back again to the blood. The capillary blood-system may be regarded as an irriga- 

 tion system, which supplies the tissues with nutrient fluids, while the lymphatic 

 system may be regarded as a drainage apparatus, which conducts away the fluids 

 that have transuded through the capillary walls. Some of the decomposition pro- 



