vitellus

Yolk, yōk, Yelk, yelk, n. the yellow part of an egg: the vitellus of a seed: wool-oil.—adjs.

From Chambers's Twentieth Century Dictionary (part 4 of 4: S-Z and supplements) by Various

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.

From Was Man Created? by Henry A. (Henry Augustus) Mott

Vit′ellary, Vitell′ine, pertaining to the vitellus, or forming such.—n.

From Chambers's Twentieth Century Dictionary (part 4 of 4: S-Z and supplements) by Various

Thus, in Fishes, the first changes consist in the segmentation of the vitellus and the formation of a germ, processes which are common to all classes of animals.

From Facts and Arguments for Darwin by Fritz Muller

"The ovarian eggs of all animals are identical, small cells with vitellus, germinal vesicle and germinal spot."

From Facts and Arguments for Darwin by Fritz Muller