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ed homoplasy to denote any superinduced correspondence of position and structure in parts embryonically distinct (other writers using the term homoplasmy). Thus, there is homogeny between the fore limb of a mammal and the wing of a bird; but the right and left ventricles of the heart in both are only in homoplasy with…

Developing, in the case of multicellular organisms, from the same embryonic systems into which the secondary unit (gastrula or plant enbryo) differentiates.

in those that are strong on both sides. Bacon. Indifferent tissue (Anat.), the primitive, embryonic, undifferentiated tissue, before conversion into connective, muscular, nervous, or other definite tissue.

The middle one of the three pairs of embryonic renal organs developed in most vertebrates; the Wolffian body.

The most posterior of the three pairs of embryonic renal organs developed in many vertebrates.

Of, pertaining to, or discovered by, Johannes Müller. Müllerian ducts (Anat.), a pair of embryonic ducts which give rise to the genital passages in the female, but disappear in the male. -- Müllerian fibers (Anat.), the sustentacular or connective-tissue fibers which form the framework of the retina.…

ned to become a part of the muscular system; -- applied to structural elements in certain embryonic forms.

One of the embryonic muscular segments arising from the protovertebræ; also, one of the protovertebræ themselves.

of or pertaining to the nose and the front of the head; as, the embryonic nasofrontal process which forms the anterior boundary of the mouth.

An opening at either end of the embryonic neural canal.

An analogous mass of protoplasm in the ovule of a flowering plant; an embryonic vesicle. Goodale.

one tissue; the residue after removal of the mineral matters from bone by dilute acid; in embryonic tissue, the substance in which the mineral salts are deposited to form bone; -- called also ostein. Chemically it is the same as collagen.

simple auditory organs of many invertebrates, containing a fluid and otoliths; also, the embryonic vesicle from which the parts of the internal ear of vertebrates are developed.

The penis or clitoris, or the embryonic or primitive organ from which either may be derived.

In embryonic development, a vesicle filled with fluid, formed from the morula by the divergence of its cells in such a manner as to give rise to a central space, around which the cells arrange themselves as an envelope; an embryonic form intermediate between the morula and gastrula. Sometimes used as synonymous with ga…

Consisting of, or having, several embryos; polyembryonic.

more embryos in one seed, due either to the existence and fertilization of more than one embryonic sac or to the origination of embryos outside of the embryonic sac.

The embryonic shell, or first chamber, of ammonites and other cephalopods.

One of the primary, or first-formed, segments of an embryonic arthropod.

The embryonic sac of an ovule, sometimes regarded as an innermost fifth integument. Cf. Quartine, and Tercine.