Lymphatics in Small Intestine of the Pig. 



113 



ducts with bulbous rounded ends extending from the mucosal plexus 

 of the center of the villi. Fig. 12, combining four consecutive sec- 

 tions of a series from an embryo 9 cm, long, shows such a vessel. 



Fig. 13. — Section of the mesentery and intestine of an embryo pig 9.5 cm. 

 long. This is an incomplete injection. It shows the size of the mesenteric 

 vessels, their course along the artery and a tertiary lymph node. D. 1. n., 

 developing lymph node. 



We see here the branches of the primary plexus near the circular 

 muscle coat, those of the secondary plexus near the base of the villi, 

 while connecting the two plexuses are vessels from which the second- 

 ary plexus is derived. From the secondary plexus the central lymph 



