1136 THE REPRODUCTIVE ORGANS 



Hon and the latter, external migration. Leopold^ has proved that the 

 latter process is possible by excising one ovary and the tube of the op- 

 posite side. Many of these animals ' became pregnant. A similar 

 case has been reported by Kelly, ^ who removed the diseased left ovary 

 and right tube of a woman, leaving the right ovary and left tube in 

 situ. Fifteen months after the operation, this woman gave birth to a 

 normal child. Seventeen months later, the left tube had to be re- 

 moved for the relief of a ruptured extra-uterine pregnancy. Inas- 

 much as the ovum does not possess an inherent power of movement, 

 its progress must be determined by outside forces, such as gravity 

 and the action of the ciliated lining of the tube and uterus. 



While much uncertainty prevails regarding the manner in which 

 the oyum gains entrance to the tube, it seems established that ex- 

 ternal migration occurs much more frequently than has been supposed. 

 In view of the preceding data, it would seem probable that the ovum 

 migrates through the narrow peritoneal spaces between the pelvic 

 viscera and may then be received by the tube of the same side as well 

 as by that of the opposite side. 



The Migration of the Spermatozoa. — In the male, the climax of 

 the coitus is reached with the ejaculation of the semen which may 

 or may not occur synchronously with the orgasm of the female. The 

 latter betrays itself by an erection of the clitoris and vaginal folds, a 

 more copious secretion of vaginal fluid by the glands of the vestibulum 

 and the glands of Bartholini, a twitching of the external bands of vaginal 

 muscle tissue (sphincter vaginae), and an alternate depression and 

 elevation of the uterus. The spermatozoa deposited in the seminal 

 receptacle, the vagina, find their way into the uterus by their own 

 activity which consists in a lateral oscillatory progression of the head 

 in consequence of the whip-like action of the tail. The latter, how- 

 ever, does not contract as a whole from side to side^ but in the manner 

 of the tail of an eel (Fig. 535). Under favorable conditions the speed 

 attained by them may amount to 4 to 10 mm. in a minute. ^ They are 

 aided in their upward movement by the mucous secretion of the uterus 

 which attracts them. In other words, this secretion exerts a positive 

 chemotactic influence upon them, whereas the sour vaginal fluid 

 affects them negatively.^ Secondly, it is a well-known fact that the 

 cilia of the uterus and Fallopian tubes beat in a direction from above 

 downward and, therefore, might retard the progress of these elements. 

 This is not so actually, because the spermatozoa are stimulated by these 

 mechanical impacts to greater activity and are capable of advancing 

 even against the direction of the stream of the intra-uterine fluid. 

 They are, therefore, positively rheotactic and thigmotactic. 



'^ Archiv fiir Gynec, xvi, 1880, 22. 



2 Operative Gynec, ii, 1898, 187. 



3 Lott, Anat. und Physiol, des Cervix uteri, Erlangen, 1871, and Henle, Lehrb. 

 der Anat., Leipzig, 1890. 



^ Chrobak, Wiener klin. Wochenschr., 1901; and Low, Stizungsb. Wiener 

 Akad., 1902. 



