DISEASES OF THE GENERATIVE ORGANS. 



DESCRIPTION OF PLATES. 

 PLATK XII: 



Fetus with its membranes at mid term. The uterus is opened on the left side. 

 In the uterus the fetus is surrounded by several membrane's, which are known 

 as the amnion or inner layer, the allantois or central layer, and the chorion 

 or outer layer. The amnion or inner membrane is nearest the fetus, and 

 forms a closed sac around it, filled with a fluid known as liquor arnnii, in 

 which the fetus floats. 



The allantois is the central membrane, and is composed of two layers which form 

 a closed sac in connection with the urachus or the tube which extends from 

 the fetal bladder through the umbilical cord. The one layer of the allan- 

 tois is spread over the outer surface of the amnion, and the other over the 

 inner surface of chorion. The allautois also contains a fluid which is known 

 as the allantoic liquid. 



The chorion is the outer envelope or membrane of the fetus, completely inclos- 

 ing the fetus with its other membranes. On the outer surface of this mem- 

 brane are found the fetal placentulte or cotyledons, which, through their 

 attachment to the maternal cotyledons, furnish the fetus with the means of 

 sustaining life. The relation of the fetal and maternal cotyledons to each 

 other is illustrated on the following plate. 

 PLATE XIII: 



Fig. 1. Uterus of the cow during pregnancy, laid open to show the cotyledons 

 (d) on the internal surface of uterus (c). The ovary (a) is shown cut across, 

 and the two halves laid open to show the position of the discharged ovum 

 at a'. 



Fig. 2. Illustrates the relation of the fetal and maternal parts of a cotyledon. 

 A portion of the uterus ( A) is shown with the maternal cotyledon (BB) 

 attached to it. The fetal portion (D) consists of a mass of very minute 

 hairlike processes on the chorion (E), which fit into corresponding depres- 

 sions or pits of the maternal portion. Each portion is abundantly supplied 

 with blood vessels, so that a ready interchange of nutritive fluid may take 

 place between mother and fetus. 

 PLATE XIV : 



Fig. 1. Taken from Fiirstenberg-Lciscrtnfj, Anatomic und Physiologic des Rindes. 

 Fetal calf with a portion of the wall of the abdominal cavity of the right 

 side and the stomach and intestines removed to illustrate the nature of the 

 umbilical or navel cord. It consists of a hollow tube (1-1') into which pass 

 the two umbilical arteries (3) carrying blood to the placenta in the uterus 

 or womb and the umbilical vein (4) bringing the blood back and carrying 

 it into the liver. The cord also contains the urachus (2'), which carries 

 urine from the bladder (2) through the cord. These vessels are all oblit- 

 erated at birth. 5, liver; 5', lobe of same known as the lobus Spiegelii; 5", 

 gall bladder; 6, right kidney; G', left kidney; 6", ureters, or the tubes con- 

 ducting the urine from the kidneys to the bladder ; 7, rectum where it has 

 been severed in removing the intestines; 8, uterus of the fetus, cut off at 

 the anterior extremity ; 9, aorta ; 10, posterior vena cava. 

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