344 GENERAL ANATOMY OF THE ABSORBENT SYSTEM. 



elastic tissue, somewhat like the structure of the dartos, which 

 allows the lymphatics to extend themselves to a great degree 

 without breaking, and subsequently to return upon themselves 

 and propel their fluid contents onwards. 



Absorbent Glands do not exist at all in reptiles and in 

 fishes. The first trace of them is met with in birds, where 

 they are formed merely by the absorbent vessels, interwoven 

 and reticulated in the form of plexus. In man, their structure 

 appears in fact to be the same, but the meshes are minute. 

 Many anatomists, as Malpighi, Cruikshank, and Werner, 

 believed there existed particular follicles, forming round cells 

 with their walls in the interior of the glands, with which the 

 vasa inferentia and efferentia communicated, and upon which 

 the blood-vessels ramified ; but nearly all modern anatomists 

 who have investigated this subject, adopt the opinions of 

 Ruysch, Hewson, Meckel, and Mascagni, that these cells are 

 nothing but artificial dilatations of the absorbent vessels, and 

 that the entire structure of a lymphatic gland consists of 

 convoluted lymphatic vessels, densely arranged, and anasto- 

 mosing freely together, over which arteries and veins ramify, the 

 whole being embraced by common cellular tissue, in the form of 

 a capsule. 



Magendie has called the attention of the profession to a fluid 

 peculiar to the mesenteric glands, and which was known pre- 

 viously to anatomists under the name of the succus proprius. 

 But Lauth has shown that this fluid does not exist in the 

 interlobular cellular tissue, and is in fact but a part of the 

 common contents of the blood-vessels, and found in all the 

 other lymphatic glands. The absorbent glands are softer and 

 larger in children and young persons than in adults, and 

 seem to diminish in number in old men. There is nothing in 

 this fact, according to Lauth, that should surprise us, since 

 the glands are made up only of convoluted vessels, which, like 

 the sanguineous capillaries, become less and less active, and 

 are here and there obliterated in the atrophy attendant upon 

 extreme old age. 

 It is as yet considered very doubtful, whether the absorbents 



