Covering Time. 101 



will be such a painful function as to ensure a struggle to 

 escape from the stallion's attentions, resulting in a 

 scrambling unsatisfactory service, which will be in a double 

 sense barren of result. 



Another very important state of affairs frequently 

 brought to light by the use of the speculum is the following : 

 The membraneous lining to the vagina is of the normal pink 

 colour, free from inflammation or offensive discharge, but 

 the os uteri, or neck of the womb, is seen projecting out into 

 the vaginal passage, erect and rigid like a piece of cartilage. 

 The effect of this erection of the os is that the passage 

 through it leading to the womb is so constricted that it is 

 almost hermetically sealed. Obviously, while this condition 

 remains, the " seed " of the stallion will have little chance 

 of entering the womb and passing thence via the fallopian 

 tubes to meet the ovum, or egg, of the mare. The normal 

 condition of the os, that is during pregnancy or during the 

 intervals between the periods of oestrum or " heat/' is for 

 its passage to be tightly closed. My physiological knowledge 

 is so meagre that I cannot attempt to give technical descrip- 

 tions of the various functions of the mare's generative 

 system ; on the other hand, my cursory study of the literature 

 of the subject, combined with practical observation, and the 

 deciphering of Nature's signs, have led me to the final con- 

 clusion that the condition of the os uteri is the key to the 

 problem, i.e., " to be or not to be " in foal. When parturi- 

 tion draws near, Nature's preparatory handiwork is shown 

 in the falling in or relaxation of the muscles on each side of 

 the mare's croup, and in the dilation of the vulva and 

 os uteri, which facilitates the passage of the foal. When 

 the mare's ovum or egg ripens or matures which stage is 

 marked by the oestrum or " heat " commencing Nature's 

 signal is the relaxation or dilation of the vulva and os uteri 



