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uteri, its back turned upwards. It also appears tliat tlie available 

 space behind the tail-end of the foetus is tilled up with about 3 liter 

 of lanugo, some of which was also adhering in places to the body 

 of the foetus. In the skin itself there were no remains of the lanugo- 

 eovering, which consisted of short, straight hairs, all of the same 

 pearl grey colour. Speckled or black hairs were not found. 



The umbilical cord has a length of ojdy 12 cm. so that the animal, 

 at the time of birth, is bound to pull out the placenta along with 

 the membranes. The skin is continued for about 1 cm. along the 

 nmbilical cord, which is compressed sideways along its whole length. 

 Taking into consideration the thickness of the umbilical cord there 

 is only a small quantity of connective tissue. The three umbilical 

 vessels are not twisted around each other. The outer surface of the 

 umbilical cord is yellowish, shining, and feels hard. 



A microscopical examination gave the following results: 



The umbilical cord is covered with an epithelium forming a pave- 

 ment of several layers, which forcibly rcuiinds one of the epithelium 

 of the epidermis. The lower layer of cells consists of high cells of 

 a somewhat cylindrical shape, lying close together, with large round 

 uuclei. Towards the siirtace the cells grow tlatter, their limits being 

 well defined in the layers immediately following the basal one. As 

 the cells flatten down, the nuclei grow less prominent. Finally, 

 forming the outside layer, there is a horny surface with lamelliform 

 structure, in which, (by means of staining with haematoxyline) the 

 remains of nuclei can be traced in places. This horny layer is sharply 

 marked off from the epithelium-layer. 



Where the amnion leaves the umbilical cord, this epithelium of 

 many layers changes into a simple epithelium. 



In the cord itself there are in section five channels of unequal 

 width and with a wall of uneven thickness. 



The two umbilical arteries and the vena umbilicalis have a very 

 thick muscular coating of circular muscle-fibres. The muscle-cells 

 show a lamelliform arrangement, the lamel li being separated b}' 

 connective tissue. 



Elastic filaments cannot be traced. Towards their lumen the blood- 

 vessels are covered Avqfh an intima, which is not clearly defined 

 towards the periphery. 



In the walls of the blood-vessels we find, almost right up to the 

 intima, the luiuina of \asa vasorum, belonging to the system of the 

 vessels proper of the umbilical cord, to be mentioned presently. 



A fourth lumen is that of the second vena lunbilicalis. The wall 

 of it clearly shows an intima, round this there is a circular nuiscular 



