VOLKMANN’S CHANNEL
Branches of arteries and tributaries of veins originated from Haversian central canals are distributed in bones inside tunnels called Volkmann's canals, that connect adjacent Haversian systems. They canals can be recognized in cross-sections of diaphyses because they are radially positioned relative to the bone outer surface and the medullary cavity.
One of these canals can be seen in the image, highlighted in red.
H - Haversian systems
I - inner or intermediate bone lammelae
Click on the link to see more on Blood circulation in bones
Diaphysis (in cross section). Schmorl's technique. Medium magnification: .
