A '''dermal bone''' (membrane bone)-
the pattern and form of bones derived from [[intramembranous ossification]] , (versus endochondral bone formed by endochondral ossification) define essential components of the [[vertebrate]] skeleton including the skull, jaws, gills, fins and exoskeleton.
The function of dermal bone is conserved throughout vertebrates, varying in shape and numbers of bones in the [[skull roof]] and postcranial structures. In [[bony fish]], dermal bone is found throughout the body in the fin rays and scales.
Dermal bone is formed within the Dermis; Grows by accretion only; outer portion of the bone depositing more by use of osteocytes
(e.g. Clavicle, Patella, os cordis)