146 



ment. Iodoform incorporated in vaseline was applied 

 at intervals of three days by means of a swab of gauze 

 introduced into tlie vagina and so manipulated as to 

 smear the salve over all parts of the vagina. Rapid im- 

 provement followed. 



About three weeks later another examination was 

 made and a few^ small transparent vesicles but little 

 larger than a pin-head were found. These vesicles 

 were kept under observation one week. No change oc- 

 curred in size, but they became somewhat more raised 

 and translucent. There was no zone of congested capil- 

 laries surrounding the vesicles, but the vaginal mucous 

 membrane remained more congested than normal. 



This is believed to be the third crop of colonies. 



Where could this renewed infection have come from? 

 The tail and external parts were carefully disinfected 

 and cleaned from all locia. Evidently the source of re- 

 infection was from the uterus (8) Fig. 12 — through the 

 OS uteri. 



There is no doubt that the microbe inhabits the 

 womb. Law and Moore found it on the "uterine mucosa 

 and foetal membranes." 



Then, the successive reinfections of the vagina is ac- 

 counted for by the fact that the microbe growing in the 

 uterus (8) is protected from therapeutic measures and 

 passing out through the os uteri (7) re-establishes a 

 footing in the vagina as soon as the field is free from 

 disinfectants. This, doubtless, also accounts for the 

 almost invariable failures, however thorough the meas- 

 ures may have been to rid aborting animals of the in- 

 fection. 



Modes of Disti'lbution. 



1. The infection may be introduced into a herd bj 

 the admission of cows or bulls from infected herds. 

 When a newly purchased cow is the carrier, whether 

 she may abort or not, transmits the disease to cows 



