64 Proceedings of the Royal Physical Society. 



of the popliteal surface, merely reversions to the type of this 

 primitive ancestor. 



Still, however much speculations may assist us in the 

 elucidation of difficult problems, they do not possess the 

 value of evidence, and although we may conclude that the 

 action of muscular attachments is insufficient to account for 

 the condition, yet further proof of its causation requires to 

 be produced. 



In the foregoing text, reference has been made to the 

 following papers : — 



1. DwiGHT, **The Range and Significance of Variation in the 



Human Skeleton," Boston Medical and Surgical Journal, 

 July 1894. 



2. DoRSEY, "A Sexual Study of the Size of the Articular 



Surfaces of the Long Bones in Aboriginal American 

 Skeletons," Boston Medical and Surgical Journal^ July 

 22, 1897. 



3. Hepburn, "The Platymeric, Pilastric, and Popliteal Indices 



of the Race Collection of Femora in the Anatomical 

 Museum of the University of Edinburgh," Jour. Anat. 

 and Phys., October 1896. 



4. Turner, Challenger Rejjorts, part xlvii., 1886. 



Turner, Journal of Anatomy and Physiology^ vol. xxi. 



p. 488, 1887. 

 Turner, " On Human and Animal Remains found in Caves 



at Oban, Argyllshire," Pi^oc. Soc. Antiq. Scotland^ 1895. 



5. Manouvrier, " Etude sur les variations morphologiques du 



corps du femur dans I'esp^ce humaine," Bull. Soc. 

 d'Anthrop. de Paris, October 1892. 



6. Scott, Transactions of New Zealand Institute, 1893, 



vol. xxvi. 



7. Dubois, '*0n Pithecanthropus erectus : a Transitional Form 



between Man and the Apes," Trans. Roy. Dublin Soc, 

 i., 1896. 



8. Hepburn, "The Trinil Femur (Pithecanthropus erectus) 



contrasted with the Femora of Various Savage and 

 Civihsed Races," Jour. Anat. and Phys., October 1896. 



9. Hepburn, "The Comparative Anatomy of the Muscles and 



Nerves of the Superior and Inferior Extremities of the 

 Anthropoid Apes," Jour. Anat. and Phys., vol. xxvi. 



