Fetal bone (labels) - histology illustration

Section of fetal bone of cat. ir. Irruption of the subperiosteal tissue. p. Fibrous layer of the periosteum. o. Layer of osteoblasts. im. Subperiosteal bony deposit. (From Quainâ'sAnatomy E. A. Schäfer.)

Histology illustration courtesy of Gray's Anatomy.