Karl Ernst von Baer disapproved Ernst Heckel's embryological evidences on evolution on what basis?

No organism except mammals experience a similar adult stage while being an embryo. Embryos never pass through the adult stages of other animals. Both 1 and 2 Karl Ernst von Baer didn't disapproved Ernst Heckel's embryological evidences on evolution .

Embryos never pass through the adult stages of other animals.

On the basis of careful studies Karl Ernst von Baer disapproved Ernst Heckel's embryological evidences on evolution giving the statement that "Embryos never pass through the adult stages of other animals".