Osteocytes have numerous cell processes but they are not seen in regular routine sections stained with hematoxylin and eosin and observed with a light microscope.
The cell bodies of osteocytes occupy the small cavities of the matrix called lacunae. Extensions of the osteocytes occupy thin tunnels called canalicles or canalicules that
connect with a neighbor canalicles. Therefore the osteocytes communicate with each other and form an extensive net inside the bone matrix. This net is very important for the bone metabolism, The bone extracellular matrix is not permeable to the transit of gases and liquids and nutrients, gases and many molecules are conducted inside the canaliculi.
The figure is of a small bone specimen specially prepared to demonstrate bone lacunae and canalicles. The specimen was placed in a solution of the dye Thionine that difused into the lacunaes of the osteocytes and of their canalicules.
What is seen in the image is the dye inside the lacunae inhabited by osteocyte cell bodies (larger arrows) and the canaliculi occupied by extensions of osteocytes (smaller arrows).
Section of a bone specimen that had been placed in thionine solution. Medium magnification.