The development of the human body; a manual of human embryology . Fig. 201.—Reproductive Or-gans of a Female Embryoof Six Months. B, Bladder; F, Fallopian tube;/, intestine; 01, ovarian liga-ment; Ov, ovary; Rl, roundligament; UA, umbilical ar-tei y ; Ur, ureter; Ut, uterus;W, Wolffian body (epoopho-ron).—(Adapted from Mihal-kovicz.) THE TESTIS. 373 chyme, and into the substance of the testis there growfrom the capsules of Bowman in the neighboring portionsof the mesonephros cords of cells which form what areknown as the medullary cords (Fig. 202, mc). One of thesecords comes into relation wit
The development of the human body; a manual of human embryology . Fig. 201.—Reproductive Or-gans of a Female Embryoof Six Months. B, Bladder; F, Fallopian tube;/, intestine; 01, ovarian liga-ment; Ov, ovary; Rl, roundligament; UA, umbilical ar-tei y ; Ur, ureter; Ut, uterus;W, Wolffian body (epoopho-ron).—(Adapted from Mihal-kovicz.) THE TESTIS. 373 chyme, and into the substance of the testis there growfrom the capsules of Bowman in the neighboring portionsof the mesonephros cords of cells which form what areknown as the medullary cords (Fig. 202, mc). One of thesecords comes into relation with each of the spherical massesderived from the epithelium, and the cells of each mass,both the epithelial and the sexual, arrange themselves ina layer surrounding the enclosing wall of mesenchyme, al- f£?J\. Fig. 202.—Section through the Testis and the Broad Ligament op the Testis of an Embryo of mm. ec, Epithelial cords; ep, epithelium; mc, medullary cords; mi, Miillerian duct; mo, mesorchium; wd, Wolffian duct.—(Mihalkovicz.) though no lumen as yet occurs in any of them. This con-dition is reached at about the sixth week, and from thistime onward until the approach of puberty, the changeswhich occur are limited to a growth in length of the med-ullary cords and epithelial masses, lumina not appearingin them until shortly before puberty. As this period approaches the final differentiation of thetestis is completed. A lumen appears in each epithelial 374 THE DEVELOPMENT OF THE HUMAN BODY. mass, which thus becomes a tubule, and the medullarycords are also transformed into tubules. The sexual cellsbegin to multiply and assume the form of spermatogonia(see p. 30), while the epithelial cells become transformedinto Sertoli cells (Benda). There is some difference ofopinion as to whether
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectembryol, bookyear1902
