vitellus

Within the shell the animal portion of the egg is found; which consists of a viscous, colorless liquid called albumen, or the white, and a yellow globular mass called the vitellus, or yolk.

Now, the human ovum or egg consists of a vitellus or yolk, which is covered by a similar membrane, known as the vitelline.

As a consequence of this superficial concentration we get segmentation of the vitellus, with the production of a morula.

The literal references to the foregoing are: am, amnion; al, allantois; v, vitellus; h, encephalon; i, eye; c, heart; f, liver; g, gizzard; ms, upper, and mi, lower member.

Up to this point the vitellus of the egg, nourished by endosmosis through its membranes, had sufficed for the nutrition of the still very small embryo.