Diagrams to show the development of male and female generative organs from a common type. (Allen Thomson.) A.—Diagram of the primitive urogenital organs in the embryo previous to sexual distinction.

• 3. Ureter.
• 4. Urinary bladder.
• 5. Urachus.
• cl. Cloaca.
• cp. Elevation which becomes clitoris or penis (Genital tubercle).
• i. Lower part of the intestine.
• ls. Fold of integument from which the labia majora or scrotum are formed.
• m, m. Right and left Müllerian ducts uniting together and running with the Wolffian ducts in gc, the genital cord.
• ot. The genital ridge from which either the ovary or testis is formed.
• ug. Sinus urogenitalis.
• W. Left Wolffian body.
• w, w. Right and left Wolffian ducts.

B.—Diagram of the female type of sexual organs.

• C. Greater vestibular gland, and immediately above it the urethra.
• cc. Corpus cavernosum clitoridis.
• dG. Remains of the left Wolffian duct, such as give rise to the duct of Gärtner, represented by dotted lines; that of the right side is marked w.
• f. The abdominal opening of the left uterine tube.
• g. Round ligament, corresponding to gubernaculum.
• h. Situation of the hymen.
• i. Lower part of the intestine.
• l. Labium majus.
• n. Labium minus.
• o. The left ovary.
• po. Epoophoron.
• sc. Corpus cavernosum urethrae.
• u. Uterus. The uterine tube of the right side is marked m.
• v. Vulva.
• va. Vagina.
• W. Scattered remains of Wolffian tubes near it (paroöphoron of Waldeyer).

C.—Diagram of the male type of sexual organs.

• C. Bulbo-urethral gland of one side.
• cp. Corpora cavernosa penis cut short.
• e. Caput epididymis.
• g. The gubernaculum.
• i. Lower part of the intestine.
• m. Müllerian duct, the upper part of which remains as the hydatid of Morgagni; the lower part, represented by a dotted line descending to the prostatic utricle, constitutes the occasionally existing cornu and tube of the uterus masculinus.
• pr. The prostate.
• s. Scrotum.
• sp. Corpus cavernosum urethrae.
• t. Testis in the place of its original formation.
• t’, together with the dotted lines above, indicates the direction in which the testis and epididymis descend from the abdomen into the scrotum.
• vd. Ductus deferens.
• vh. Ductus aberrans.
• vs. The vesicula seminalis.
• W. Scattered remains of the Wolffian body, constituting the organ of Giraldès, or the paradidymis of Waldeyer.