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coating, and tlien. i-iLjht round this, a coatiiifi; of bundles of muscles 

 running lengthwa^'s, but not adhering close together. In the walls of 

 this vena I have not noticed anv bloodvessels. In the lumen I found 

 here and there some blood-corpuscles. In following np this i)artlv 

 obliterated vena towards the foetus, it is found to divide itself into 

 two branches shortly before the foetal insertion of the umbilical 

 cord; the two branches run together a little way down, then one of 

 them splits up again and three branches can be traced right up to 

 the front abdominal wall, where tiicy lose themselves. Towards the 

 placenta this vena also s})lits np into ramifications, which grow finer 

 and finer and finally branch off into the tissue of the umbilical cord. 



The fifth lumen in the umbilical cord is situated in the foetal half 

 between the two umbilical arteries ; towards the placenta these apj)roach 

 each other and the vessel runs alongside of them. This lumen is 

 of an irregular shape, somewhat compressed and provided with an 

 epithelium composed of cells that are flattened and arranged in several 

 layers, the respective limits not being distinctly defined. 



This lumen runs right through the cord till close to the placenta 

 wdiere it suddenly stops. There is no communication between this 

 lumen and the yolksac. That we have here a continuation of the 

 allantois-channel is proved by its original position between the two 

 umbilical arteries, which position I also noticed inside the abdominal 

 wall. I did not notice any remains of a yolk duct with certainty. 



The stroma of the umbilical cord consists of cellular tissue with 

 exceedingly fine fibrils [)ursuing a circular course, underneath the 

 epithelial coating this circular direction is dexiated from and the 

 curve becomes irregular. Round the vessels there is no distinct system 

 of circular fibres. Between the two arteries the character of the 

 stroma changes somewhat, it is of a looser construction and contains 

 a few longitudinal bundles of smooth muscular tissue. These can 

 best be seen by staining with polychrome methylen-blue (Unna) and 

 can be traced right through the whole cord. By the side of this the 

 profusion of the bloodvessels belonging to stroma funiculi proper 

 seems remarkable. 



These vasa proprid funiculi umhilicaVn^ are met with right along 

 the funiculus, most of all in the foetal part. They appear to be con- 

 nected with the vasa of the subcutaneous cellular tissue of the abdo- 

 minal wall. Arteries as well as lai-ge veins filled with blood are 

 noticeable. The dislribution is somewhat irregular. Especially round 

 the umbilical vessels they are heaped up together, entering the walls 

 close up to the intima. I have not been able to ascertain the existence 

 of a connection between the vasa propria funiculi and the vasa 



