46 OBSTETRICAL ANATOMY. 



from its fringed or dentated border. This pavilion is fixed to the ex- 

 ternal side of the ovary, and its inner surface is marked by numerous 

 narrow, close-set, minutely plicated laminae, while its circumference is 

 irregularly disposed into a number of unequal prolongations or fringe 

 (^fimbricE) which hangs into the abdominal cavity. This arrangement is 

 interesting, from the fact that it gives us a unique example of a breach 

 of continuity between a gland (the ovary) and its excretory canal (the 

 tube). 



Each tube is composed of three tunics : an external or serous.^ formed 

 by the broad ligament; a middle or muscular, constituted by longitudinal 

 and circular non-striated fibres, continued from those of the uterus, 

 which are also disseminated in the pavilion and its fimbriae ; and an 

 internal or mucous, which exhibits longitudinal rugae in the tube, and 

 radiated in the pavilion ; this membrane is covered by ciliated epithe- 

 lium, and its villi are greatly enlarged after impregnation. It ceases 

 abruptly at the margin of the fimbriae, where it meets the peritoneum. 



The blood-vessels supplying the Fallopian tubes are derived from the 

 ovarian arteries, and their nerves are from the great sympathetic. 



T\v€\x function is to convey the spermatozoa of the male to the ovary 

 in the first instance, and afterwards to transmit the impregnated ovum 

 to the uterus or its horn ; in this respect they are the excretory ducts of 

 the ovaries. When the Graafian vesicle of the ovary ruptures, the fim- 

 briae of the tube grasp the ovary, and receive the ovum, which they 

 carry to the ovarian extremity of the canal ; this act, together with the 

 application of the pavilion to the ovary, takes place either through the 

 contraction of the non-striated muscular fibres which this part contains, 

 or from the swelling of the bulb of the ovary. At times, however, the 

 act is not properly accomplished, and the fecundated ovum, instead of 

 passing into the uterine cavity, escapes the fimbriae and falls into the 

 abdomen, where it constitutes that most remarkable form of gestation 

 termed extra-uterine. 



Differences. 



Cow, Sheep, and Goat. 



In the Cow, Sheep, and Goat, the fimbriated extremity of each tube is 

 expanded upon the outer margin of the ovarian capsule ; the inner sur- 

 face of the pavilion is beset with numerous fine oblique striae, and is 

 further increased by narrow folds of laminae converging toward the con- 

 tracted opening of the duct. The duct itself forms three or four wavy 

 folds, and is then continued along the walls of the wide ovarian capsule 

 to the extremity of the uterine horn, which makes an abrupt curve to 

 meet it. 



Pig- 

 In the Pig the oviduct has but few or no inflexions, but its length is 

 proportionately greater than in the other species. The pavilion is wide 

 and deep, and the margin of its abdominal opening is almost even ; its 

 inner surface is augmented by many long, narrow, and highly vascular 

 folds, which radiate from the commencement of the contracted part of 

 the tube upon the expanded pavilion. 



Bitch. 

 In the Bitch the fimbriated commencement of the oviduct is attached 



