[Melanosis of the large intestine].

Studies of 100 appendices and 20 snips of the large intestine in cancer (17) and in Hirschprung's disease (3) were carried out, which showed that enterochromaffin cells containing greyish-brown pigment in cytoplasm, constituted the permanent constituent of the epithelial linings of these organs. A possibility of phagocytosis of this pigment by macrophages of the connective layer of the mucous membrane is described. Basing on the analysis of literature data and her own findings the author comes to the conclusion that the phagocytoused enterochromaffin pigment in macrophages of the mucous membrane corresponds to the so-called melanin of the large intestine. This is evidenced from the similarity of histochemical reachions and the pattern of distribution of the said pigment and the enterochromaffin cells. An analogy with epiphysis is drawn, where as a side product of serotonin--melanin, a specific pigment, is also formed.