I on n< ■ B. Saot'n. 



primar) lympha tern in rabbits, the i at and the pig, this papei 



has three important points: First, the discovery thai the early lym- 



- are filled with blood, which has proved to be of Buch value, 



a that it> ; i- understood. Second, the discovery of the 



retroperitoneal sac which he described as lying adjacent to the mesen- 



ic veins. Be also showed the iliac sacs and cisterns chyli; all of 

 which we now know tunic from the renal veins (Sabin L36). Third, 

 he ooted that lymphatic ducts when they are reconstructed from - 

 tions appear a- a row of beads. Since these rows of beads occurred 



mg ili.' veins in his reconstructions ami since he could nut find the 

 connections of the early sacs with th< veins lie was led to suggest that 

 lymphatics might arise from multiple anlagen splil off from the veins 



mg their course. The apparently i~"laic<l endothelial-lined vessels 

 found in serial sections we 'all Meyer-Lewis anlagen. 'They arc dis- 

 ■i \ I I 1 . 



The jugular sac in rabbits has an early extension along the primitive 

 ulnar \< in like thai of the human embryo. The dorsal portion of the 

 sac, I'"!- the posterior triangle of the neck, arises Erom a large stalk 

 from the primary jugular portion between the level of the ith ami 5th 

 cervical iici 



I. Pbimabt Lymphatic System i\ ihe Cat. 



The primary lymphatic system in the cat will be described from the 



extensive work of Euntington ami McClure (51-58 ami 91-94), one 



instruction of Lewis (76) and a few injections of my own. The 



work of Euntington and McClure has been mainly on the development 



of the jugular lymph sacs and the thoracic duct in the cat and their 



servations are for the most pari broughl together in two extensive 

 papers (54 ami 58). Their work is difficult to analyze ami cannot 

 be done entirely accurately without seeing their sections. They have 

 relied mi the appearances of sections ami the appearances of wax modi 

 from them 1" differentiate lymphatics, ami since these are nut ade- 

 quate criteria it is impossible to he BUre that all the structures shown 



lymphatics are lymphatics; in fact, one can he certain that some "i' 



them are n.it. Their theories in regard to il rigin ami development 



of the lymphatic system ari' discussed in sec. VIII. In the article 

 (.Mi on the jugular lymph sac of the eat figs. 8 to vM may he disre- 



fled a- evidence, since thej are diagrams. Figure 22, which they 



