PREGNANT UTERUS 37 



Draw the section, color the germ layers and label all the 

 arts. 



2. The Pregnant Uterus 



Uteri containing embryos three or four inches in length 

 may be obtained from any large slaughter house. The 

 whole uterus with the ovaries should be secured. If they 

 are preserved and hardened for a few days in ten per 

 cent, formalin, then transferred to three or four per cent, 

 formalin, and finally soaked in water three or four days 

 before using, they will be well preserved and most of the 

 disagreeableness of the formalin preservatives will be 

 removed. It is well to change the water some two or 

 three times. 



Examine the uterus and note that it is composed of two 

 rather large tubes united at one end and free at the other. 

 These are called the horns of the uterus. The horns are 

 united at the vagina. Along the inner edge of each horn 

 is a broad, tough, flat membrane which causes the outer 

 edge to form a ruffle. This membrane is the broad 

 ligament. The location of the embryos in the uterus is 

 indicated by the enlargements. Note the many branched 

 blood vessels beneath the surface of these enlargements. 

 Trace one horn of the uterus to the free end. It will be 

 seen that the horn suddenly narrows down into a tube 

 which is about the size of a large knitting needle. This 

 tube is the Fallopian tube or oviduct. The Fallopian 

 tube ends distally in a thin membrane which surrounds 

 the ovary, with the exception of an opening into the body 

 cavity. This terminal opening is the ostium tub 03 ab- 



