A lack of uniformity in the blood picture in tuberculous meningitis has been frequently noted in the Babies' Hospital during the last three or four years. The variations were so frequent and inexplicable that an effort was made to establish an average figure for the blood count in this condition. For this purpose 169 cases of tuberculous meningitis from the records of the hospital for the last eight years were analyzed. In the course of this work additional facts of interest were obtained, and as they help in some measure to explain the variations in the blood picture of the disease in question, they are worthy of record.
There were 252 counts made on the 169 cases. The average leukocyte count was 20,900 per c.mm. with an average polynucleosis of 72.6 per cent. Only ten, or 4 per cent., of the counts were below 10,000, and twenty, or 8 per