ABSORBENT SYSTEM. 267 



temporaries furnished us, as well as themselves, by their praise- 

 worthy exertions in the cause of science, with materials to fill up 

 this lamentable hiatus in veterinary anatomy. Professor Girard, 

 whose " Traitt d'Anatomie Vtterhiaire " does no less credit to 

 the talent and industry of its author than honour to the veteri- 

 nary school over which he presides, has presented us with an 

 article on the ramification of the lymphatics, which I shall trans- 

 late, and take the liberty to transcribe into this place. 



The Thoracic Duct, 



The largest, longest, and most remarkable of the lymphatic 

 vessels, in which terminate the majority of the lymphatics of the 

 body, is situated within the thorax, on the right side of the dorsal 

 vertebrae, between the aorta and the vena azygos : it receives the 

 lymphatics from the posterior extremities, pelvis, parietes, and 

 viscera of the abdomen, head, neck, withers, and left anterior 

 extremity. 



It takes its origin under the loins in a dilatation or sinus, very 

 variable in its form and dimensions, situated at the root of the 

 great mesenteric artery, named the receptaculum chj/li ; it directs 

 its course forward, enters the thoracic cavity by the aortic per- 

 foration through the diaphragm, extends along the bodies of the 

 dorsal vertebrae until it arrives opposite to the base of the heart, 

 where it curves downward to cross over to the left side, in its way 

 to the anterior opening of the thorax, and, as it leaves the spine 

 for this purpose, runs obliquely over the trachea and esophagus ; 

 having reached the left side, it stretches forward to the beginning 

 of the anterior vena cava, and terminates, against the middle of 

 the anterior border of the left first rib, in the base of the left axil- 

 lary vein : not infrequently, it ends in the right axillary ; in 

 some instances, even in the beginning of the anterior cava. At 

 its termination it dilates and forms a sinus, whose mouth, open- 

 ing into the vein, is guarded by a broad valve so disposed as to 

 prevent any reflux of blood into the duct* : it has also a ligament- 

 ous band around it at this part, which confines it to the vein re- 

 ceiving its contents. 



This canal shews but little uniformity in its cahber : in some 

 places it is strait, in others varicose. And it is not uncommon to 

 find it detaching one and even several branches in its course, 

 large or small, which either remain separate, or else, after running 

 a certain distance, rejoin the main channel. 



* Notwithstanding this valve, blood often gains admittance into the canal : 

 this is observable in all cases of violent death, or in which struggles and 

 convulsions attend expiration. 



