70 Diseases of the Genital Organs 



of which is not at present known. At the apex of each 

 cornu, the tip of the chorion is necrotic and is commonly sur- 

 rounded by exudate or pus. It would appear that such an 

 area would offer but little resistance to invasion and once 

 the bacteria have reached the allantoic fluid, the very thin 

 amnion offers scant barrier. 



Placental Hemorrhage. At the cervical end of the 

 uterus there also exist conditions which apparently favor 

 invasion of the fetal sac. Nearly always placental hemor- 

 rhages exist at the os uteri internum and some of the cotyle- 

 dons have separated. In this manner the placental areas, 

 denuded of protective epithelium, and with important vol- 

 umes of blood resting upon their surfaces, offer an inviting 

 field for invasion. 



Uterine Sand. Such placental hemorrhages must be 

 of very frequent occurrence. It would be supposed that such 

 hemorrhage would be resorbed in a few days so that the 

 regular meeting with them would seem to indicate that they 

 occur almost constantly. The frequency of these is further 

 suggested by the existence in the utero-chorionic space in 

 essentially all cows in advanced pregnancy, of bodies I have 

 designated uterine sand. These are free, spherical bodies 

 generally about one-sixteenth inch, translucent and amber- 

 colored. They are very hard, are insoluble in water and 

 alcohol. They vary greatly in numbers and volume. By de- 

 taching the fetal membranes from the uterus, washing both 

 surfaces in a vessel of water, and then decanting it off, 

 there remains behind a mass of uterine sand varying from 

 half a dram to one ounce, feeling much like sand when 

 grasped between the fingers. Its exact character and origin 

 are unknown but it appears most probably due to disinte- 

 gration of red blood cells, and if so, indicates frequent and 

 important placental hemorrhages. 



In ruminants, therefore, with the immense utero-chori- 

 onic space, the inter-cotyledonal area of the chorion offers 

 the avenue of least resistance to the invasion of the fetus. 

 In the soliped, where no non-placental area exists, any vul- 

 nerable field must be created by the invasion of the placental 



