Ophthalmoscopic examination may reveal a choked disk. Spinal puncture shows increased pressure by fluid very frequently coming through the hollow needle with a spurt, and clear or slightly cloudy. Following such a puncture the patient is very often much improved for from a half an hour to a whole day, but the symptoms soon return. A complete examination of the cerebrospinal fluid thus removed, will aid a great deal in diagnosis. This includes the following: 1. Remove about 25 c. c. at spinal puncture. 2. Make several slides and stains for organisms, as septic and tubercular. 3. Examine and count the endothelial cells, leucocytes, and pus cells. 4. Make cultures. 5. Make a Noguchi (butyric-acid) test for excess of albumin. 6. Make a Lange colloidial test. 7. Wassermann, Nonne, and Noguchi tests for syphilis. 8. Test for sugar. 9. Test for total acidity and relative acidity. 10. Cholin may be tested for. In the serous form one will find the cells increased somewhat, especially the leucocytes, but the micro-organisms are conspicuous by their absence. The Lange (colloidal-goldchloride) test will show the characteristic color reaction of a septic process. The Noguchi (butyric-acid) test will be positive. Excess of albumin. The Wassermann, Nonne and Noguchi tests for syphilis are negative. (Unless such a case should be a complicated one.) The test for sugar is very important in that in serous meningitis sugar is present. The relative acidity is not markedly affected, and cholin is not present, or, if so, in only small quantity. (b) _Septic meningitis._--If this is _localized_, and there is a collateral serous meningitis associated with it, then the symptoms may be the same, as just described; however, the cerebrospinal fluid will show a greater degree of irritation, and the fluid may contain some micro-organisms. The majority of localized septic meningitis cases, however, are not as severe in their course as the serous or diffuse septic forms. The one important symptom is the localized headache, which is quite persistent, and the greater rise in the temperature. There are, undoubtedly, many cases of localized meningitis that show a perfectly normal cerebrospinal fluid, and most of the cardinal symptoms absent; and these are the cases that usually get well or lead to extradural abscesses subsequently.