THE VESSELS. ^ 



found, that the Proper Vessels are not true vessels, but 

 peculiar modifications of the cellular tissue, which we 

 shall afterwards describe under the name of Receptacles 

 of proper juices. We shall only comprehend, then, 

 under the collective name of Vessels, those which have 

 been long described under the name of Lymphatic 

 Vessels ; but as this appellation, founded on the function 

 which is attributed to them, is itself only hypothetical, 

 we shall not adopt it, since it becomes useless the 

 moment that the Receptacles of proper juices are no 

 longer confounded with the vessels. 



These vessels, termed Lymphatics, have been de- 

 scribed in English, by Grew, under the names of Sap 

 Vessels or Lymph-ducts : others have named them 

 Sap Vessels (vaisseaux seveux); and jVIirbel describes 

 them under the name of Great Tubes (grands tubes). 

 Kieser comprehends them collectively under the name 

 of Spiral Vessels (vaisseaux spiraux), which is only 

 applicable to one of the forms under which they are 

 presented to us. These vessels present five very distinct 

 varieties of form, viz. — 



1st. Trachea (tracMes). 



2d. Annular or Striped Vessels (vaisseaux annu- 

 laires ou ray is). 



3d. Dotted Vessels (vaisseaux ponctues). 



4th. Strangulated, Moniliform, or Necklace- 

 like Vessels (vaisseaux en chapelet). 



5th. Reticulated Vessels (vaisseaux reticulaires). 



We shall commence by describing them separatelj' ; 

 then we shall occupy ourselves with discussions which 

 divide anatomists upon their reciprocal relation, their 

 history, and their use. 



