1. Fresh, plasma-stored, and saline-stored calf bone heterografts did not produce osteogenesis in the anterior chamber of the rat's eye. They did produce a host inflammatory and fibroblastic reaction.
2. Storage of heterogenous bone in homologous bovine plasma increased, whereas storage in saline solution decreased, the inflammatory reaction produced.
3. The inflammatory reaction was greater with the large-fragment cancellous bone heterografts than with the large-fragment cortical implants suggesting that the amount of surface area of bone implant exposed to the host tissue is significant.
4. Fragmentation of heterogenous bone also increased the inflammatory and foreign-body reaction.