PfiOCESS OF EVOLUTION OF THE UTERUS 



11 



In the non-pregnant uterus, in the Fallopian tube are 

 found numerous small prominences resembling scars or warts; 

 their color is lighter than that of the uterine mucosa ; they are 

 of a longish shape, their long axis being at a right angle to the 

 long axis of the tabe. In cows which have borne sevferal 

 calves they are more distinct than in the heifer. These are 

 the cotyledons, or carunculaa ; into their surface the villi of the 

 chorion are inserted. During pregnancy follicles form at the 

 site of the cotyledons. Each mass of follicles enlarges, 

 becomes movable and pedunculated. Since the cow has 



Fig. 3. — Cotyledon of a non-pregnant Uteru3, cross section. (Mag. 57). 

 ((, Ciliated epitlielium ; Z>, connective tissue with several cells ; c, blood vessels. 



numerous cotyledons in every tube — 40 to 60 — respectively 

 placentae maternse, one speaks of a multiple placenta {placenta 

 multipla). The cotyledons are convex. Their surface shows 

 numerous depressions and is covered with pavement epi- 

 thelium. The cotyledons do not contain any muscle tissue : 

 this is very important to explain the expulsion of the afterbirth 

 in the cow. It will be discussed fully (retention of the after- 

 birth) under its proper head. When single placentae, respect- 



