[Scanning electron microscopic description of the surface of the cavum leptomeningeum]

1. After fixation with formalin or gluteraldehyd and OSO4 the cavum leptomeningeum of pig and cow has been investigated. The obtained specimen were dried in critical-point-method. 2. The results were quite congruente to the literature when we magnified the specimen with slight magnification. The trabeculas and membranes go to the Arachnoidea in a diverging way. Moreover we have found the following phenomena: 3. The mesothelium of the cavum leptomeningeum possesses microvilli and pored gaps. 4. The fragility of the mesothelium and the danger of producing artefacts in preparation has been observed.