There isn't a specific gland that solely stores white blood cells. However, several organs and tissues play a crucial role in the production, storage, and maturation of white blood cells (also known as leukocytes):

* Bone marrow: This is the primary site of white blood cell production.

* Spleen: The spleen stores white blood cells and filters the blood, removing old or damaged cells. It also acts as a reservoir for lymphocytes.

* Lymph nodes: These small, bean-shaped organs are scattered throughout the body. They filter lymph fluid and house lymphocytes, which are a type of white blood cell.

* Thymus: This gland is important for the maturation of T-cells, a type of lymphocyte.

Therefore, while there's no single "white blood cell storage gland," these organs and tissues work together to maintain a healthy population of white blood cells in the body.