THE FEMALE 



49 



Photograph of Rana pipiens female body cavity at the height of ovulation. 



is found between the heart and the lateral peritoneum, at the apex 

 of the liver lobe. At this anterior end is a slit-like infundibulum or 

 ostium tuba with ciliated and highly elastic walls. The body cavity 

 of the female is almost entirely lined with cilia, each cilium having 

 its effective beat or stroke in the general direction of one of the ostia. 

 These cilia are produced in response to an ovarian hormone and 

 therefore are regarded as secondary sex characters. They are found 

 on the peritoneum covering the entire body cavity, on the liver, and 

 on the pericardial membrane. There are no cilia on the lungs, the 

 intestines, or the surface of the kidneys except in the ciliated peri- 

 stomial (peritoneal) funnels which lead into the blood sinuses of the 

 kidneys. The abundant supply of cilia of the female means that eggs 

 ovulated from any surface of the ovary will be carried by constant 



