from the GNU version of the Collaborative International Dictionary of English
- n. A primeval larval form; a double-walled sac from which, according to the hypothesis of Haeckel, man and all other animals, that in the first stages of their individual evolution pass through a two-layered structural stage, or gastrula form, must have descended. This idea constitutes the Gastræa theory of Haeckel. See gastrula.
from The Century Dictionary and Cyclopedia
- n. In biology, a hypothetical animal form assumed by Haeckel as the ancestor of all metazoic animals — that is, of those which pass through or attain to the morphological form of a gastrula. See gastrula.
Sorry, no etymologies found.