The dermis is a layer of skin between the epidermis (with which it makes up the skin) and subcutaneous tissues, and is composed of two layers, the papillary and reticular dermis[WP].

http://upload.wikimedia.org/wikipedia/commons/2/23/EpidermisPainted.svg

Consider adding a layer-of-skin grouping class for all skin layers

A collagenous layer of the skin subjacent to the epidermis and covering the hypodermis. It contains various types of cells (e.g. fibroblasts, pigment cells, nerve, blood vessels and scales. Le Guellec et al, 2004.[TAO]

vertebrate dermis

uberon

cutis, corium

dermal

When approaching controversies surrounding skin evolution, we need to remember that the skin consists of two layers, an epidermis and a dermis, not a single evolving structure. (...) It is little wonder that controversies about homology exist. If we think of the epidermis, the dermis, and their interactions as an evolving unit, then their specialized products (hair, feathers, and reptilian scales) are broadly homologous.[well established][VHOG]

UBERON:0002067

http://purl.obolibrary.org/obo/uberon.owl, http://purl.obolibrary.org/obo/cl.owl

• hypodermis

• zone of skin

• future dermis

• skin epidermis