part_of part of part of contained in existence overlaps material entity dorsal ventral margin of the whole animal tissue anterior region of the whole animal posterior compartment of the whole animal juvenile head prepharyngeal region parapharyngeal region tail secretory system adult hermaphrodite asexual adult copulatory region adhesion gland PMID:20865784 https://orcid.org/0000-0003-2569-1939 | https://orcid.org/0000-0002-7535-4411 Planarian_Anatomy marginal adhesive gland OCLC:16809160 Groupings of specialized epithelial cells located along the dorsal ventral margin. Adhesion glands are comprised of three cell types, the viscid and releasing gland cells which penetrate through an epithelial anchor cell and terminate at the epidermal surface. ISBN:9780070316607