286 CIRCULATORY SYSTEM. 



the division is rather superfluous. There is also a distinction 

 of the lymphatics, arising from their situation, as in the veins; 

 some of them are called superficial, and the others deep-seated. 

 The arrangement upon which this nomenclature depends, is 

 found in the head, trunk, extremities, and in the most of the vis- 

 cera. The deep-seated trunks are the largest, but the least nu- 

 merous. 



- 



Of the Lymphatic Glands. 



The Lymphatic or Absorbent Glands or Ganglions, some- 

 times called waxen kernels in common language, are an appen- 

 dage of a very important description to the absorbent system. 

 They are flattened ovoidal bodies, of a reddish ash colour, in- 

 durated so as to afford a strong resistance to pressure, and of a 

 variable volume, from a line'to twelve lines in their long dia- 

 meter. They are found principally in clusters or chains, and 

 more abundantly in the neck, in the groin, in the arm-pit ; in the 

 mesentery, and about the bifurcation of the trachea. 



The lymphatic vessels, in their course towards the thoracic 

 duct, have to pass through one or more of these glands. This 

 rule is almost universal; some exceptions, however, to it, in the 

 case of the lower extremity, have been stated by Mr. Hewson, 

 and in the case of the back, by Mr. Cruikshank :* the latter be- 

 lieves Mr. H. to have been under a misapprehension in this 

 statement concerning the extremities, as it had not been verified 

 by the result of his own investigations. The vessels that enter 

 into the glands are called vasa inferentia, while those that de- 

 part from them are the vasa efferentia. As, owing to the jux- 

 taposition of many of these glands, the vessels between them 

 are very short, this distinction would likewise seem almost su- 

 perfluous, because there is scarcely space to apply the term ef- 

 ferentia,. before the same vessels enter the consecutive gland, 

 thereby becoming inferentia. For the most part, the vasa in- 

 ferentia are more numerous and somewhat smaller than the ef- 

 ferentia. The former, as they enter the gland, radiate into 

 smaller branches, while the latter are formed from the junction 

 of smaller branches. 



Anat of Absorb. Vessels, second edit. p. 79. London, 1790. 



