part of cuticular extracellular matrix medial layer of collagen and cuticulin-based cuticle extracellular matrix cellular_component The fluid-filled cuticle layer that lies between the cortical and basal layers and is characterized by the presence of regularly spaced columnar struts that lie on either side of the annular furrows and link the two surrounding layers. In C. elegans, a defined medial layer is found only in adult animals. medial layer struts GO:0060109 cellular anatomical structure