28 INTRODUCTION TO SEXUAL PHYSIOLOGY 



found in the enlarged epithelial cells which form the luteal cells 

 of the yellow body. In the ovaries of many species of mammals 

 epithelioid interstitial cells are also present in the stroma. 



The Fallopian tubes or oviducts, the function of which is to 

 convey the ova to the interior of the uterus, open internally into 

 the body cavity close to each ovary. The discharged ova enter 

 the fimbriae or enlarged ends of the tubes, which are believed to 

 expand and erect so as to receive the ova as they are released. 



Fig. 16. — Young Imnian Ciliaahan follicle. The ca\ity contains 

 the liquor follicuH. (From Sellheim.) 



The oviducts are lined internally by a ciliated epithelium outside 

 of which are connective tissue and unstriated muscle. Cilia 

 are also present on the insides of the fimbrioo, their function 

 being to direct the ova into and down the tubes which contain 

 a certain amount of fluid secretion. In some animals (dog, 

 ferret) the ovaries are enclosed by a membranous covering 

 which is continuous with the tubes, an arrangement which ensures 

 the passage of the eggs into the tubes and prevents them from 

 becoming lost in the body cavity as occasionally happens in other 

 species. The tubes in man are about 4 inches long. 



