Stereometry of the red pulp on the human spleen. I) Methodological remarks.

The principal histometrical formulas to be applied to the analysis of human spleen's red pulp are illustrated. The discussion particularly concerns the formulas to evaluate the following measures per unit splenic volume:volume of the elements; surface area of sinus-splenic cord boundaries; mean breadth of cords; length of the sinus; mean sectional area of the sinus. Suggestions are given about the criteria to be followed in the proper assumption of the data which must be subjected to statistical estimation.