General Infections of the Genitalia of Sheep and Goats 725 



with those of McFadyean and Stockman, though the conclu- 

 sions drawn from them may vary. We secured no uniform- 

 ity of result and kept no controls. The spirillum may have 

 been present in the genital tract of the one ewe prior to in- 

 oculation. McFadyean and Stockman appear to believe that 

 the death of the ovine fetus is brought about by one microbe 

 and its maceration by others. Perhaps this belief is general 

 in abortion in all animals and possibly is borrowed from ob- 

 servations upon post-natal death. There a given infection 

 commonly causes death and other bacteria (usually already 

 present in the body, as the colon bacilli in the intestines) re- 

 leased from the restraint of the living tissues quickly break 

 down the cadaver. 



Intra-uterine death presents a quite different problem. 

 Putrefaction or maceration of the embryo is dependent upon 

 the invasion of the cadaver by putrefactive bacteria, just as 

 in post-natal life, but the invasion is subject to important 

 limitations because the embryo physiologically is hermeti- 

 cally sealed within the uterus. McFadyean and Stockman 

 apparently believe that, when the embryo perishes in the 

 uterus, the cervical canal opens and permits free invasion 

 from the exterior. My observations lead me to believe that 

 abortion is associated either with a cervicitis which pre- 

 vents the formation of the uterine seal or with a cervical 

 endometritis which destroys the uterine seal. In the first 

 instance it is highly probable, if not certain, that the bac- 

 teria of pyocervicitis can cause fetal putrefaction and macer- 

 ation as well as metritis, chorionitis, fetal dysentery, sepsis 

 and death. In the second instance the bacteria incarcerated 

 within the sealed gravid uterus, which have power to cause 

 endometritis, destruction of the uterine seal and fatal dis- 

 ease of the fetus, quite certainly possess putrefactive or 

 macerating powers. This is well illustrated in the macera- 

 ting embryos in swine. These largely occur at the cervical 

 or ovarian end of the uterus, but may occur in the middle 

 of an embryo row, flanked upon either side by apparently 

 healthy embryos. These macerate, putrefy and, if not too 

 old, are absorbed, but they are wholly shut off from invasion 



