We analysed the tibial cartilage of 5 juvenile and 10 adult non-degenerative knees for morphometric criteria. Determination of cellular and nuclear total volume per unit cartilage volume,, number of cells and nuclei per unit cartilage volumen and cellular and nuclear single volumen of chondrocytes in the superficial and basal cartilage layer was done in relation to their being covered by meniscus. We found cells and nuclei and their total volumen in the superficial layer constantly smaller, number of chondrocytes and nuclei constantly higher than in the basal layer. This was clearly seen in the meniscus-covered part of cartilage, less marked in the central non-covered part. In adults the central cells are superficially hypertrophic and gain few individual and total volume in the basal layer. These superficial central cells are on a high level of metabolism, synthesising much intercellular substance, but they prostrate in basal direction. The aging chondrocyte is maximal adapted to the strain and uncapable to react to further load.