346 TERMINATION OF THE ABSORBENTS. 



by Hewson, Cruikshank, and others ; namely, that the absorb- 

 ent and venous systems, can be considered as connected only 

 by the principal lymphatic trunk, the thoracic duct, which 

 opens into the left subclavian vein, and by the right brachio- 

 cephalic, and other branches, which open into the internal 

 jugular and subclavian of the right side. All other communi- 

 cations which take place between them may be received as ex- 

 ceptions to the normal structure. 



The most frequent of these, are the branches between 

 the thoracic duct, and vena azygos. In many amphibia and 

 reptilia, lymphatic hearts, or dilatations of the absorbent vessels 

 that are capable of contracting somewhat like a heart, have 

 been discovered by Miiller, which assist in the circulation of the 

 lymphatic fluid.* Nothing analogous to them, has, however, 

 been discovered in man. 



The bodies connected with the absorbent vessels, which are 

 called Conglobate Glands, are generally of a roundish, or irre- 

 gular oval form, and somewhat flattened. They are of various 

 sizes, from two lines in diameter to more than twelve. Their 

 color is frequently whitish, but sometimes it is slightly 

 inclined to red. They are invested with a covering of cellular 

 membrane, which appears like a membranous coat ; and they 

 are connected to the contiguous parts by a loose cellular sub- 

 stance. When the absorbent vessels connected with these 

 bodies approach near to them, they divide into a number of 

 ramifications, most of which enter into the substance of the 

 gland, while some of them run over it. On the opposite side 

 of the gland a number of branches go out, which unite and 

 form trunks similar to those which entered the gland. The 

 vessels which enter the gland are called Vasa inferential, and 

 those which go out of it Vasa efferentia. 



These vessels are generally much convoluted in the sub- 

 stance of the glands, so that those' bodies sometimes appear 

 like a mere convolution of absorbent vessels. There has been 



* See an interesting paper on this subject by Dr. Allison of Philadelphia 

 Amer. Jour. Med. Science, Aug. 1838. 



