24 ANATOMY OF THE LYMPHATIC SYSTEM. 



dividual spindle-shaped element rolls on its broadside so as to appear 

 as a placoid, and vice versa. Having so determined that all the 

 elements of this gelatinous hyaline body are of the same nature, a 

 further question arises, What is the significance of those elements ? 



From what has been said until now, it is plain that this gelatinous 

 body is perfectly analogous with what is called ' Schleimgewebe,' 

 namely, what is regarded as embryonal connective tissue ; but we must 

 venture to repeat again that we have not been able to discover a 

 transition of the cellular elements of that gelatinous body into con- 

 nective tissue bundles. The significance of the placoid cellular ele- 

 ments of it is to become transformed into fat cells. 



If we examine a preparation taken from the perfectly hyaline 

 part of the neighbourhood of a fat lobule we find the nearer we ap- 

 proach to the fat lobule the more numerous are the branched placoids, 

 which contain fat globules, either one large one, or several small ones. 

 First they appear only isolated, the protoplasmic part and the processes 

 of the cell are very distinctly recognisable, the nucleus is situated 

 somewhat peripherally ; then we find them lying in groups, they are 

 still provided with processes, but contain a very large fat globule. 

 Here the protoplasm of the cell-body is reduced to a more or less thin 

 covering of the fat globule. Where cells of that kind lie close beside 

 each other, their processes can hardly be made out ; but where these 

 are met with as isolated ones it does not require any high power to 

 convince one's self that they are still provided with processes. 



Where these new fat cells lie in groups a great number of blood- 

 vessels are to be met with : they form in such places a special system, 

 which is perfectly analogous to that found in fat lobules. But there 

 exist similar systems of blood-vessels in groups which do not contain 

 fat cells, which contain only clusters of the previously-mentioned 

 placoids : here they are, however, provided only with fewer and shorter 

 processes. One finds, for instance, an arterial branch breaking up 

 into a bunch of capillary vessels, which, after anastomosing with each 

 other, collect themselves into a venous vessel. The hyaline matrix 

 in which this system of blood-vessels is imbedded contains a great 

 number of branched placoids. Jn such places it can be further made 



