THE COMPARATIVE HISTOLOGY OF THE FEMUR 



By DR. J. S. FOOTE 



professor of histology and pathology, creighton medical college, 

 omaha, nebraska 



(With Three Plates) 



The comparative study of the minute structure of the femur was 

 begun by the present writer in 1909. The first report described 46 

 microsections of the femora of as many different animals and was 

 published in the Transactions of the American Microscopical Society 

 of April, 191 1. Following the first report and largely upon the sug- 

 gestion of Dr. Ales Hrdlicka, Curator of the Division of Physical 

 Anthropology in the United States National Museum, the writer has 

 extended his investigations to man of different ages and races, as well 

 as to many additional genera and species of animals ; and an abstract 

 of these further studies which revealed many important and new 

 points, is here presented. 



For the valuable material, facilities for study, and courtesies 

 extended, the writer is especially indebted to the Division of Physical 

 Anthropology of the United States National Museum; and to the 

 Division of Mammals and Reptiles of the same institution ; the 

 Departments of Reptiles, Birds, and Mammals of the American 

 Museum of Natural History, and the Departments of Anatomy and 

 Medicine of the Northwestern, the Tulane, and the Creighton Uni- 

 versities. 



The total number of genera and species whose femora have up to 

 this date been examined amounts to 400, including amphibians, rep- 

 tiles, birds, mammals, and man. The observations have been made 

 on complete cross-sections of the femur at the middle of the shaft. 

 Embryological, adolescent, adult, and senile bones of the same species 

 were examined whenever it was possible, and controlling studies were 

 also made on other bones of the body. The drawings have been made 

 for the most part with the aid of the Edinger apparatus. 



The investigations, which are of pioneer nature, have brought out 

 many facts that are new to science. The existence of three types of 



Smithsonian Miscellaneous Collections, Vol. 61, No. 8 



