Haversian canals

Haversian canals, minute passages in the outer bone layers. The canals carry blood to the inner bone tissue through combined efforts of blood and lymph vessels, nerves, and connective tissues. The canals are surrounded by bone tissue; together they make up a compact bone structure called the Haversian system, or osteon. The structure is named for the English physician Clopton Havers, who first noted the canals in the 17th century.