section of a female’s oviduct between the isthmus and the vagina where water is added to the albumen and then the hard calcium carbonate shell is laid down on the outer shell membrane, surrounding the ovum, yolk, membranes, and albumen; a thin protein-rich layer called the cuticle covers the hard shell to prevent infection from penetrating the shell’s pores; the egg spends most of its time in the uterus before oviposition; also called the shell gland; an area between the vagina and the uterus, the uterovaginal junction, can store sperm from a male to be moved up the oviduct later to fertilize an ovum in the infundibulum