A little more than twenty years ago, Dr. Hamann1 described and illustrated a most remarkable condition in the skeleton of the lower limbs, involving most conspicuously the femora. The specimen in question, now E 386 of the Hamann Museum, is still in many ways an enigma, and apparently is quite as unique as when described for the first time by Dr. Hamann. My reasons for reviving this subject are briefly as follows: The original account of these femora was characteristically brief and concise, and it concerned itself only with the more essential and significant features; however, the rarity of the condition and its apparent significance seem to call for a more extended consideration. In addition to this, I believe that it is possible to offer something in the way of explanation. Before detailing my own observations on these bones, I shall quote most of the original article verbatim; except