Ablastica - Metazoa without germ layers

The germ layers theory is a fundamental synthesis of comparative and evolutionary embryology, which is essential for proving the unity of the multicellular animals. In this article, we substantiate the point of view that among Metazoa, in addition to Diploblastica and Triploblastica, there is a third group, which lacks germ layers, and on this basis we propose to call it Ablastica.