ovoviviparity

…more primitive condition, known as ovoviviparity and found in certain snakes, is the simple retention of the egg until it hatches. In this case the embryo derives food from the yolk present in the egg and is not dependent on the mother except for physical protection. Compare oviparity.

…may be oviparous (lay eggs), ovoviparous (retain the eggs in the body until they hatch), or viviparous (have a direct tissue connection with the developing embryos and give birth to live young). All cartilaginous fishes—the elasmobranches (e.g., sharks, rays, and skates)—employ internal fertilization and usually lay large, heavy-shelled eggs or…

…drying is the adoption of ovoviviparity, or the hatching of eggs within the parent’s body.

…other than the skates are ovoviviparous (that is, the egg hatches within the mother). In this case, the egg is first coated in the shell gland with a temporary membranous capsule that lasts only during early development. After emerging from its capsule, the embryo remains in the oviduct of the…