The Muellerian Ducts 25 



a. The rid nets, formed from the anterior or ovarian ex- 

 tremities of the Muellerian ducts, are two long, tortuous 

 tubes, varying in length and other characters according to 

 species. Their length is much greater than the distance 

 from the anterior extremity of the uterine cornu to the 

 ovary. This distance is fixed by the utero-ovarian liga- 

 ment. In some animals the oviducts are naked and clearly 

 visible. In the bitch they are hidden in the abundant fat 

 of the broad ligament. The utero-ovarian ligament in the 

 dog and cat is very short, so that the anterior end of the 

 uterine cornu is virtually in contact with the ovary, while 

 the oviduct, 3 to 4 inches in length, is thrown into numerous 

 folds, to terminate in the immediate region of its origin, so 

 that casual observation, without dissection, might lead to the 

 assumption that the oviduct was well-nigh absent, whereas 

 it is very similar in actual length to that of other species. 

 When divested of any concealing coverings of peritoneum, 

 fat, or other tissues, the oviduct appears as a very convo- 

 luted white cord about 0.1 inch in diameter. It is very firm 

 to the touch and gives a sensation much like its analogue 

 in the male, the vas deferens. After it is dissected out from 

 the surrounding tissues and its numerous abrupt curves are 

 carefully eliminated, a very fine sound, as one of the tail 

 hairs of a horse, may be inserted at one opening and passed 

 through its entire length. While technically the oviducts 

 complete a communication between the peritoneal cavity and 

 the exterior, the tubes are ideally impassable, except to ova 

 and spermatozoa. They do not under usual conditions per- 

 mit the forcing of liquids through their canal when intra- 

 uterine injections are made under comparatively high pres- 

 sure. Clinically, they also offer valuable resistance to the 

 passage of bacteria. Frequently, pathogenic organisms, 

 such as those involved in abortion and retained placenta in 

 cows and other animals, travel along the oviducts, causing 

 disease of them or, reaching the ovary, induce abcess or other 

 disease, causing sterility. 



The intimacy of contact between the peritoneal covering 

 of the oviduct and the muscular walls varies according to 



