Figure 7.1 in One pretty amazing T. rex

Figure 7.1. Medullary bone in extant laying hen. (A) Gross cross section of femur of actively laying hen shows extensive medullary bone formation. New bone is randomly oriented and much more porous than overlying cortical bone. (B) Low magnification and (C) high magnification of histological section of demineralized bone from laying hen. Chemical differences between cortical and medullary bone are indicated by differential response of each bone type to hematoxylin and eosin staining. In (C), separation of the medullary bone from cortical bone is seen as sectioning artifact. Large, multinucleated osteoclasts are visible around bone spicules, and small osteoblasts align along preexisting bone spicules, active in deposition of new bone. Abbreviations: CB, cortical bone; MB, medullary bone; ELB, endosteal laminar bone; OCL, osteocyte lacunae; OC, osteoclast; OB, osteoblast. Scales as indicated. See color version of this figure in the accompanying CD-ROM.Published as part of Mary Higby Schweitzer, Jennifer L. Wittmeyer & John R. Horner, 2008, One pretty amazing T. rex, pp. 92-100 in Tyrannosaurus rex, the tyrant king, lndiana University Press on page 92, DOI: 10.5281/zenodo.394326