OK, I have to admit that I'm still puzzled after looking at this pair of photos for quite a while.  I actually went to the trouble to make this composite so I could see them side by side in close to the same scale.  I'm pretty sure that they are different versions of the same photo despite the fact that the backgrounds are quite different and the shading on his lower legs is not the same. Of course, the most obvious difference is the fig leaf's size, shape, and color.  We know that fig leaves were sometimes added to nude photos back in the day by retouching.  (Yes, they could do that in 1900.)  And after all that, I'm still left wondering if someone photoshopped it more recently.  

We'll see another set like this a bit later.