Along with the paralysis and atrophy of the muscles, there appear also, as the result of the destruction of the nerve trunks, _trophic affections of the bones and of the skin_. The changes in the skin have been already described; when the anæsthesia is advanced, there always appear ulcerations under the heel and the ball of the foot. Most of these owe their origin simply to pressure; the weight of the body is too much for the atrophic skin. They are always callous, heal with great difficulty, and so long as the patient goes about, not at all. The ulcers are not usually deep, but it may happen that they penetrate as far as the bone, and lead to necrosis. But usually necrosis of the bones is preceded by periostitis, and when the pus makes its way out, an ulceration leading down to necrotic bone is formed. We have sometimes seen the formation of a blister precede the ulceration, but it is rare, and it is certainly not true, as stated by many authors, that ulceration of the sole is always preceded by a bulla. Not only on the feet but also on the hands, necrosis with exfoliation of bone takes place; the phalanges are especially attacked. When the atrophy of the muscles is advanced, the fingers are always claw-like, with extension of the first phalanx. The joints consequently often _appear_ swollen, although no joint affection is present. The phalanges and the metacarpals undergo simple atrophy, becoming very thin at the middle, and since the joints retain almost their normal thickness, they appear swollen by contrast. As already noted, this clawing of the fingers is accompanied by no disease of the tendon sheaths. The bones in the feet undergo the same form of atrophy.