224 HENRY K. DAVIS 



Group III 



Breschet ('36) describes a thoracic duct as seen by Haller 

 which was double in its caudal portion. The thoracic duct in 

 this case start in the abdominal cavity as two ducts, which 

 pass cephalad into the thorax, one lying on each side of the 

 aorta. In the cephalic portion of the thorax, the left duct crosses 

 over to the right side and the right and left ducts both open 

 into the left angulus venosus. This form of duct belongs to 

 Type 3 (fig. 3). I found no ducts of this type among my own 

 cases and could find no other cases described in the literature. 



Group IV 



Butler ('03), Lauth ('35), Patruban ('44), Diemerbroeck ('85), 

 Cousin ('98), and Walther (described by Haller '46), describe a 

 thoracic duct which starts in the abdominal cavity as a single 

 trunk and passing cephalad into the thorax on the right side of 

 the aorta divides into two branches at about the level of the 4th 

 thoracic vertebra. The right branch opens into the angulus 

 venosus on the right side and the left branch passing dorsal to 

 the aorta opens into the angulus venosus of the left side. The 

 type of duct described by these investigators belongs clearly 

 to Type 4 (fig. 4). I found no ducts of this type among my 

 own cases. 



Group V 



The thoracic duct in this type starts in the abdominal cavity 

 as a single duct and passing cephalad into the thorax on the left 

 side of the aorta divides into two branches. The right branch 

 opens into the right angulus venosus and the left branch into the 

 left angulus venosus. I have been unable to find ducts of this 

 type described in literature and there were none among my own 

 cases. 



