External genitalia in both male and female are formed from the genital tubercle, genital swelling and genital folds. The genital tubercle becomes the phallus. In the male it continues its development until it is fully grown and forms the penis with the  penile urethra opening at its tip (i.e. tip of penis). In the female it grows for a little while and stops further growth to allow the the urethra to develop outside its walls in the anterior wall of the vagina. In both it leads to the formation of similar phallic structures such as the corpora cavernosa and the corpus spongiosum. In the female the Mullerian tubercle becomes the hymen and moves to the surface. The genital fold then becomes the labia minora while the genital swellings become the labia majora. In the male, the genital tubercle becomes the penis, genital swelling the scrotum and the genital fold the penile urethra.