[A simple method for measuring the surface areas of membranes in histology demonstrated on the calf hypophysis].

The work carried out with the hypophysis of three calves to demonstrate that a sharp border line does not exist between Adeno- and Neurohypophysis. The result of these experiments show that on the average 57,1% of border line is of connective tissure and the remaining area lacks this type of membrane. In the border area lacking connective tissue, basophil Adeno-Hypophysis cells play an important role in transporting the secretion from Adeno- to Neurohypophysis. The basophil infiltration in the pars posterior are in the form of spread branches which could distinctly be seen; The infiltrating cells are in group or in the form of solid line rather than the isolated form, while the single cells could be noticed around the formers. These cells penetrate only a short distance in Neurohypophysis. The basophil Adenohypophysis cells lose their shape and original charakteristic gradually as they farther infiltrate in, and finally dissolved and considered as a holocrine secretion.