ABSTRACT
In previous we could observe that many researches were interested in the phenomena of absorption that occur in the mesothelial that involves the viscerae. We already made some researches empliying some chemical substances like the lanthaum nitrate and the osmium amine. With the utilization of the lanthanum nitrate we came to the conclusion that the penetration of this heavy salt is impeded by the presence of the basement membrane that separates the mesothelial from the connective tissue. This membrane, as observed at that time, is continous that separates the mesothelial from the connective tissue. This membrane, as observed at that time, is continous with the basal lamina located between mesothelial cells. Our observations led us to the conclusion that the salt traveled through the cytoplasm and not in between neighbouring mesothelial cells. The observations made in the material treated with osmjium-amine, were comapred to those made with the employment of the lanthanum nitrate. In general, no reaction was observed in any of the techniques employed, with the exception of some special cases. Int he later the osmium amine reacts in the outer surface of the mesentery but also penetates with no visible reaction, all the way to the connective tissue to react with the elastic layer. In the present paper, where tha colloidal iron was employed, int he mesothelial cells and in the connective tissue. We are comming to a final conclusion that the permeability of different layears of tissues is of a great variety and of a great capacity of selectiveness