thymus medulla morphology trait Hassall's corpuscle morphology trait Hassall concentric corpuscle morphology trait Trait.ontology Any measurable or observable characteristic related to the shape, structure, color, or pattern of the small spherical bodies of epithelial cells found in the medulla of the thymus, that are arranged in a concentric pattern around clusters of degenerating lymphocytes, eosinophils and macrophages. thymic corpuscle morphology trait VT:0009539 Hassal body morphology trait Virchow-Hassall body morphology trait thymus epithelium morphology trait