Picture of a Womb Nest

A yinrih womb nest, a highly derived egg-sac with its own simple heart and circulatory system. A central bus artery feeds oxygenated blood to the kits, and returning veins pass through a semi-permeable dermal layer to allow for gas exchange. The arrangement of kits in the womb nest is what gives womb ships their name, as suspension capsules are arranged in a similar manner.