46 INTRODUCTION TO SEXUAL PHYSIOLOGY 



recognisable by its yellow colour (Corner). The uterus also 

 undergoes changes indicative of an abbreviated pseudo-pregnancy, 

 these consisting mainly of growth of the glands, followed by 



Fig. 26. — Section through uterine mucosa of dog forty-eight days after 

 the end of prorestrum (retrogressive stage of pseudo-pregnancy). 

 Many of the glands are degenerating ; their hiniina contain colloid 

 and the remains of desquamated epithelial cells. Extravasated 

 blood is seen in the stroma. (From Marshall and Hainan.) 



regression at the approach of the next heat. Mammary changes 

 of a similar kind have also been observed, and these, like those of 

 the uterus, are correlated with the development and involution 

 of the corpus luteum. In the cow bleeding, chiefly from the 

 vagina, has been observed after oestrus, and this is believed to 

 mark the termination of a previous shortened pseudo-pregnancy 



