1906.] Communication on Regeneration of Bone. 239 



No bleeding, aseptic healing without visible scar. Osseous union solid at 

 end of fifth week. The left fore limb of each is preserved for comparison. 



Description of specimens as seen 12 weeks after transplantation of bone 

 grafts : — 



Right Radius of D. — Layer of fibrous tissue covering whole of shaft of right 

 radius and so firmly attached that scalpel as well as periosteal elevator were 

 required to denude the bone. Shaft is entire and continuous from one 

 epiphysis to the other, but there is great thickening at the part where the 

 graft from neighbouring bone was introduced. In marked contrast to the 

 dense, firmly adherent new formation of connective tissue surrounding the 

 right radius on this limb was the thin periosteal covering of the left radius 

 which shelled with great ease on the application of the periosteal elevator. 



Description of specimen E is very similar to that of D. 



Right radius of E. — Dense layer of new formation of fibrous tissue covering 

 bone and firmly adherent to the shaft. Shaft united throughout, but presents 

 large irregular node at seat of bone grafting. 



F and G. — Transplantation of Bone en masse. 



Two dogs, F and G, of different species had the periosteum entirely removed 

 from the right radius, after which the greater portion of the shaft of the right 

 radius, extending from near the proximal to near the distal epiphyses was 

 removed en masse and transplanted, the shaft of the right radius of F 

 being inserted into the gap in the shaft of G, and the shaft of the right radius 

 of G being introduced into the gap in the radius of F. 



No vessels requiring ligation. Aseptic healing, leaving no visible or 

 adherent scar. Bone firm at end of four weeks, and subsequently increase in 

 circumference was in F detected through soft tissues. The left radii are 

 preserved for comparison. 



Description of Specimens. — Eight radius of F seen 11 weeks and 1 day after 

 transplantation. New formation of dense connective tissue closely adhering 

 to the bone and with difficulty elevated therefrom. The shaft, continuous 

 with the epiphyses and firmly united thereto, is greatly increased in circum- 

 ference, and is much thicker than the radius of the left limb from which the 

 normal periosteum is easily raised in one piece by the elevator. 



G. — Eight radius of G seen 20 weeks and 4 days afterwards. Newly formed 

 connective tissue closely adherent to the transplanted shaft. The diaphysis 

 is united throughout, and so perfect is the union at either end that the 

 insertion can scarcely be made out. It looks like a well formed normal 

 shaft. 



