Gynaecology for students and practitioners . ick swellings—the genital folds—the cloacal membrane is pushedsomewhat into the depths (backwards) {see Fig. 58, ). By theunion of the urorectal septum with the cloacal membrane the latteris divided into urogenital membrane anteriorly, and anal membraneposteriorly. The former is the first to dehisce, and thus the sinusurogenitalis opens externally prior to the gut. The genital papillaacquires a blunt free end, which is the future glans clitoridis {see Fig. 59,). Its surface, which looks towards the sinus urogenitalis. 84 GYNiECOLOGY becomes
Gynaecology for students and practitioners . ick swellings—the genital folds—the cloacal membrane is pushedsomewhat into the depths (backwards) {see Fig. 58, ). By theunion of the urorectal septum with the cloacal membrane the latteris divided into urogenital membrane anteriorly, and anal membraneposteriorly. The former is the first to dehisce, and thus the sinusurogenitalis opens externally prior to the gut. The genital papillaacquires a blunt free end, which is the future glans clitoridis {see Fig. 59,). Its surface, which looks towards the sinus urogenitalis. 84 GYNiECOLOGY becomes furrowed and presents two lateral borders. The groovebetween these borders is lined by epithelium and becomes the urethralgroove, the borders themselves become the urethral lips. From the genital folds the labia majora develop, whilst theurethral lips become the labia minora {see Fig. 60). The length ofthe urogenital sinus diminishes more and more, but the upper part, that between the opening of the ureter and the Miillerian promi-. CLITORIS LABIUMMINUS HYMEN Fig. 60. Development of the External Genital Organs(Kollmann). Female fcetus of the sixteenth week. nence, stretches considerably in length {see Fig. 61, urethra). A circularfurrow divides this section of the urogenital sinus into a proximalpart, the trigone, and a distal part, the urethra. Through the re-duction in length of the lower segment of the sinus urogenitalisand through the gradual increase in width of this portion of the canal,Miillers prominence recedes more and more upwards, and comes tolie finally in the floor of a short wide pouch. From the epithelium ofMiillers prominence develops the hymen,^ whilst the short pouch below,which is nov/ the sole remaining part of the original sinus urogenitalis,becomes the vestibide and fossa navicularis. The former is muchdeeper in the newborn than in adults. The septum urorectale widensout to form the perineal body and perineum {see Fig. 60). The Ligaments. At a ce
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectgynecology, bookyear1
