Quain's elements of anatomy . Fig. 815.—Development of the ex- Fig. 815. TERNAIi SEXUAL ORGAXS IX THE MALEAND FEMALE FROM THE IXDIFFEEENT TYPE (from Ecker). A, the external sexual organs in anembryo of about nine weeks, in wliichexternal sexual distinction is not yet es-tabUshed, and the cloaca still exists ; B,the same in an embryo somewliat moreadvanced, and in whicli, without markedsexual distinction, the anus is now sepa-rated from the uro-genital aperture ; C,the same in an embryo of about ten weeks,showing the female tj^pe ; D, the samein a male embryo somewhat more ad-vanced. Throughout
Quain's elements of anatomy . Fig. 815.—Development of the ex- Fig. 815. TERNAIi SEXUAL ORGAXS IX THE MALEAND FEMALE FROM THE IXDIFFEEENT TYPE (from Ecker). A, the external sexual organs in anembryo of about nine weeks, in wliichexternal sexual distinction is not yet es-tabUshed, and the cloaca still exists ; B,the same in an embryo somewliat moreadvanced, and in whicli, without markedsexual distinction, the anus is now sepa-rated from the uro-genital aperture ; C,the same in an embryo of about ten weeks,showing the female tj^pe ; D, the samein a male embryo somewhat more ad-vanced. Throughout the figures the?following indications are employed ; pc,common blastema of penis or clitoris;to the right of these letters in A, theumbiUcal cord ; p, penis ; c, clitoris; cl,cloaca ; ng, urogenital opening ; a, anus ; Is, cutaneous elevation which becomes labium or scrotum ; I, labium; s, scrotum ; co,caudal or coccygeal united by median fusion, of the scrotum in the male. The lips of the urogenitalfurrow, which in the female are converted into the nymphfe, and in the maleunite as integument below the penis, are both at first precisely the same in allembryoes. In the open condition, which continues until the eleventh or twelfthweek, the parts appear alike in both sexes, and resemble very much the moreadvanced female organs. The nidiments of Bartliolin s or Coivi)ers glands is said, seen at an early period, near the root of the rudimentary clitoris orpenis, on each side of the genito-uriuary passage. In the female, the two external folds of integument enlarge, so as to cover theclitoris as the laMa majora. The clitoris itself remains relatively smaller, and thegroove on its under sm-face becomes less and less marked, owing to the openingout, and subsequent extension backwards, of its margins to form the vascular bulbs, sunk more deeply in the tissues, remain distinct and
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Keywords: ., boo, bookcentury1800, booksubjectanatomy, booksubjecthumananatomy
