COMPOSITION AND PROPERTIES OF THE CHYLE AND LYMPH. 451 



destitute. And in Mammals, the plexuses almost entirely disappear, and their 

 place is occupied by the " glands" which are found in the course both of the 

 lacteal and lymphatic Absorbents. These bodies, wherever they occur, have the 

 same essential structure; and may be described as consisting of convoluted 

 knots of absorbent vessels, their simple cylindrical canals, however, being usually 

 dilated into larger cavities or "cells" that freely communicate with each other; 

 and capillary vessels being minutely distributed among them. These blood- 

 vessels have no direct communication with the interior of the absorbents and 

 the cavities of the glandulae, being separated from them by the membranous 

 walls of both sets of tubes ; but there can be no doubt that transudation readily 

 takes place from one set of canals to the other. The epithelium, which lines 

 the absorbent vessel, undergoes a marked change where the vessel enters the 

 gland; and, according to Prof. Goodsir, 1 becomes more like that of the proper 

 glandular follicles in its character. Instead of being flat and scale-like, and 

 forming a single layer in close apposition with the basement-membrane, as it 



Fig. 136. 



Diagram of a Lymphatic gland, showing 

 the intra-glandular network, and the 

 transition from the scale-like epithelia of 

 the extra-glandular lymphatics, to the 

 nucleated cells of the intra-glandular. 



Portion of intra-glandular Lymph- 

 atic showing along the lower edge 

 the thickness of the germinal mem- 

 brane, and upon it the thick layer of 

 glandular epithelial cells. 



does in the absorbents previous to their entrance into the gland and after their 

 emergence from it (Fig. 136), we find it composed of numerous layers of spher- 

 ical nucleated cells (Fig. 137), of which the superficial ones are easily detached, 

 and appear to be identical with the cells found floating in the Chyle ( 475). 



474. Composition and properties of the Chyle and Lymph. The chief chemi- 

 cal difference between these fluids consists in the much smaller proportion of solid 

 matter in the Lymph, and in the almost entire absence of fat, which is an im- 

 portant constituent of the Chyle. This is well shown in the following compara- 

 tive analyses, performed by Dr. Gr. O. Rees, 3 of the fluids obtained from the 

 lacteal and lymphatic vessels of a donkey, previously to their entrance into the 

 thoracic duct; the animal having had a full meal seven hours before its death. 



Water 



Albuminous matter (coagulable by heat) 

 Fibrinous matter (spontaneously coagulable) 

 Animal extractive matter, soluble in water and alcohol 

 Animal extractive matter, soluble in water only . 



Fatty matter 



Salts ; Alkaline chloride, sulphate and carbonate, with 

 traces of alkaline phosphate, oxide of iron 



Chyle. 

 90.237 

 3.516 

 0.370 

 0.332 

 1.233 

 3.601 



0.711 

 100.000 



Lymph. 



96.536 



1.200 



0.120 



0.240 



1.319 



a trace. 



0.585 

 100.000 



1 " Anatomical and Pathological Observations," p. 46. It has recently been denied by 

 Prof. Bennett, however, that these cells are epithelial, or given off from a basement-mem- 

 brane such as that described by Prof. .Goodsir (2 119); their formation being, in Prof. 

 Bennett's opinion, from nuclei developed freely in the midst of the fluid. (See "Edinb. 

 Monthly Journ., March, 1852, p. 284.) 



2 "Medical Gazette," Jan. 1, 1841. 



