THE CIRCULATORY SYSTEM IN BONE 



By J. S. FOOTE, M. D. ' 



Professor of Pathology, Medical Department of Creighton University, 

 Omaha, Islebraska 



(With 6 Plates) 



INTRODUCTION 



This article on the circulatory system in bone is the result of a 

 continued study of the comparative histology of bone published in a 

 monograph entitled " A Contribution to the Comparative Histology 

 of the Femur," Smithsonian Contributions to Knowledge, Vol. 35, 

 No. 3, 1916. 



In that monograph were described the structural bone types and 

 the type combinations as they were observed in cross sections of the 

 femora of various animals from amphibians to and including man.^ 

 The circulation within the bone substance was not seen at that time, 

 as cross sections do not show it properly. 



In 1919 a casual preparation of a tangential section of the femur 

 of a domestic turkey disclosed a very remarkable circulation in the 

 bone substance and it was this disclosure that led to further examina- 

 tion of tangential sections of the bones of different animals, the draw- 

 ings and descriptions of which are here presented. 



Later (1919-20) the structure of and circulation in the bone of the 

 fish, as seen in the Mascalonge, Esox, were studied, compared with 

 ithe bone types of later vertebrate animals and added to the list of 

 bones examined. 



THE CIRCULATORY SYSTEM IN BONE 

 The circulatory system in bone, as usually described, is limited to 

 the blood vessels of periosteal membranes, medullary canals and 

 diploe of long and cranial bones respectively, little being known about 

 the circulation within the bone substance itself. 



The circulation described in this article is situated in the bone 

 substance of the mandible and cranial bones of the fish, Mascalonge, 

 Esox, in the walls of the long bones of the amphibian, reptile, bird, 



* Number of sections of femora described and drawn in the monograph, 440. 

 Smithsonian Miscellaneous Collections, Vol. 72, No. 10 



