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 Moreover, the boundaries of the cutaneous analgesia were no longer definite, but were made up of islets, or points, of sensation. Passing from the area of complete loss to parts normally sensitive to a prick, the pin struck spots, where it produced a slowly developed, dull but painful sensation. If, however, this particular spot was not struck, it might be that sensibility was not encountered until another spot was reached, some millimetres nearer the unaffected parts of the limb.

On June 14, fifty days after the operation, the gradual shrinking in extent of the cutaneous analgesia on the arm was found to have continued (figs. 6, 7 and 8), although the borders of the loss of sensation to cotton wool remained entirely unaltered. The loss of sensation to cold corresponded in extent with that of the loss to prick; but, wherever the part was feebly sensitive to 'the latter stimulus, sensibility to cold seemed to be absent. To all degrees of heat the borders of the loss of sensation had remained unchanged, and the extent of the anassthesia, even to temperatures between 50° C. and 60° C, uniformly exceeded that of the loss to prick.

On the flexor surface of the .forearm, there was nothing to show that cold could be appreciated within the border of cutaneous tactile anaesthesia. In the first interosseous space, cold was certainly appreciated well inside the limits of the loss of sensation to cotton wool; the border of the loss to cold lay about midway between that for cotton wool and that for prick.

By July 20 (eighty-six days after the operation), there was no part of the forearm where a prick could not be occasionally appreciated, although in many places this form of sensation was extremely defective. Moreover, considerable changes had occurred in the condition of the hand ; the whole of the thumb and the skin over the radial half