=Spinal neurosyphilis:= Not only the spinal cord but also the posterior and anterior nerve roots exhibited severe lesions. These lesions were both meningeal and parenchymatous. The meningeal process differed in its intensity in different parts of the spinal cord, being severest in the thoracic region. At one point in this region, the dura mater was so firmly attached to the pia mater that the line of demarcation between the two membranes was hard to make out. In fact, it seems clear that there could have been no free intercommunication between the spinal fluid above these adhesions of dura to pia mater and the spinal fluid below the adhesions. Accordingly, it seems that _lumbar puncture_, had it been practised in this case, _would have failed to show features representative of the whole cerebrospinal fluid system_. Moreover, since at no point in this region of adhesions or in the pia mater of the spinal cord below this point, were found any lymphocytes, it seems clear that the ordinary lumbar puncture would have failed to reveal a pleocytosis. Whether this fluid would have yielded a positive globulin and excess albumin test, it is now impossible to say; but it appears that the process in the lower part of the spinal cord was to all intents and purposes extinct. However, there was one region of more severe inflammatory involvement. The _spinal cord in the cervical region showed a lymphocyte infiltration_ of its vessels amounting to a mild myelitis (meaning, thereby, an inflammatory process of the spinal cord remote from the pia mater). Moreover, in this region, there was, besides the perivascular infiltration of the substance, also an infiltration of the overlying membranes themselves, especially in and near the posterior root zones. The lessons of this finding are several: The inflammatory process in this case does not appear to have been entirely extinct! Can we not suppose that treatment might still have benefited this local inflammation (perivascular infiltration of the cervical spinal cord substance and overlying lymphocytic meningitis)? Can we not also picture the gradual ascent of the inflammatory lesions from lower segments to higher segments and possibly conceive of the gradual elevation of the zone of hyperæsthesia manifested in this case as following the gradual displacement upward of the lymphocytic process? Are there spirochetes in this tissue? So far none have been discovered, possibly through inaccuracies of available technique. To the neuropathologist, however, the lesion looks like a local reaction to organisms. In addition to the spinal meningitis, chronic and acute, as above described, there were extensive parenchymatous spinal lesions.