A Granular condition of the ventricular ependyma, especially that of the fourth ventricle, has long been recognised as one of the most important of the post-mortem lesions of general paralysis. In the opinion of the writer it is present in at least 90 per cent. of the cases, and the more carefully the examination of the ependyma is made, the greater will be the percentage of cases showing granulation in asylum post-mortem books. In the Journal of Mental Science, July, 1905, the writer recorded the frequency of this condition in an analysis of 131 consecutive post-mortems on male paralytics at Wakefield Asylum, and on 112 male and 19 female cases at Horton Asylum. The percentages were 878, 90, and 100 respectively. Blatchford (Journal of Mental Science, 1903, p. 483) states 70 per cent. of paralytics were recorded as exhibiting granular ependyma, and of the non-paralytic deaths 16·6 per cent. of men and 5·3 per cent. of women. There were 83 paralytic deaths and 369 non-paralytic. The writer is convinced that granularity of the ependyma, especially that of the fourth ventricle, is the most valuable naked-eye diagnostic sign of general paralysis. This statement is supported by that of Bolton, who considers the most characteristic naked-eye sign of dementia paralytica to be granularity of the ventricular ependyma, referring specially to the lower half of the fourth ventricle.