46 Proceedings of the Royal Irish Academy. 



flanging, and (b) pilastering is noteworthy. One would expect a powerful 

 gluteus maximus in a squatting people. 



4. Platymeria is relatively uncommon among modern bones. In this 

 collection it was well marked, and the lateral and medial flanges occurred 

 separately. 



The association of trochanter tertius and fossa hypotrochanteriea with 

 the lateral flange leads one to believe that the gluteus maximus has some 

 influence in its production, though I do not believe that it alone will 

 produce it. 



The condition of the medial femoral flange in some of these bones 

 suggests its production by alterations in the relative attachments of the 

 vastus medialis and intermedius. 



5. The association of the rough depression at the lateral side of the gluteal 

 ridge with the size and extent of the lateral flange suggests that it may have 

 some influence on the formation of the latter. 



6. Probably the cause of the medial flange is not a single one; its 

 presence is not due to development of muscles alone. The position of the 

 flange, its occurrence occasionally among modern specimens, and the appearance 

 of the bone on section would suggest that it may also act as a supporting 

 factor or buttress. It seems less marked in bones with a distinct forward 

 curvature of the shaft ; sections of the flange show the cancellous arches 

 passing more definitely and strongly to this region than in ordinary 

 specimens, suggesting that the bone had been subjected to marked twisting 

 movements. In habitual squatting there would be maintenance of the femur 

 for long periods in a rotated position. 



7. The amount of pilastering is moderate, and is only noteworthy in that 

 it bears out former statements as to the likelihood of platymeria and 

 pilastering being due to different causes. 



8. The deep impressions for the posterior cruciate ligaments and the small 

 facet at the back of the internal condyle both bear out the assumption of a 

 frequently flexed condition of the knee-joint in these people. 



9. The distinct platycnemia appears to be associated with strong 

 development of the tibialis posticus and flexors, the strength of these 

 muscles leaving its impress on both tibia and fibula. The occurrence of these 

 conditions (increase in strength of muscles in posterior crural region) may be 

 explained either by assuming the adoption of the squatting attitude or 

 frequent running exercise in an active race. The various other points 

 detailed indicate that the former is here most likely to be the correct 

 explanation. 



