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Florence R. Sabin. 



right to form the inferior vena cava, and shows that the sacs now 

 extend forward almost to the cisterna chyli. The cistema chyli 

 being median and the posterior sacs being lateral, the plane of the 

 section made it impossible to trace whether the connection has been 

 made or not. The two sacs, however, run to the same level and 

 probably do connect. The posterior sac measures 4.6 x. 2 (lateral 

 X .9 (dorso-ventral). In the angle where the femoral vein branches 





Fig. 16. Coronal section through the posterior lymph sacs as they lie 

 along the primitive sciatic veins, of the same embryo, at a level shown in 

 Fig. 21. X about 49. S. 1. p., saccus lymphaticus posterior ; V. c, vena 

 candalis ; V. s., vena sciatica primitiva. 



off from the primitive sciatic is a lymph node and it will be seen 

 that deep lymphatic vessels follow both the sciatic and femoral veins. 

 There is also a group of superficial lymphatics covering the skin 

 of the hip in the groove between the body wall and the leg. These 

 superficial lymphatics could be traced to a connection with the sac on 

 the opposite side, but not on the side reconstructed. This gap 

 is probably due to the accidental plane of the section ; it comes where 



