We a r e accustomed to consider senile alterations of the human body as self-evident results of attrition, just as the deterioration of any structure exposed to incessant wear-and-tear. Atrophy of organs, their hardening (sclerosis), stiffening, o r rarefaction, and discoloration due to changes in their physical properties and in their chemical composition, seem to be no more noteworthy than the deterioration of any timeworn article in our daily experience.Since 1953, we have collected, investigated and classified material from approximately 1,000 postmortems on aged persons who died at the Warren State Hospital, Warren, Pa. We have encountered not only well-known and often reported senile phenomena, but also disorders unrecognized o r neglected until now, which have revealed new aspects of aging. We have very often Dbserved decrease in the excretory pancreatic tissue, a typical disease probably impairing the digestion of fatty and lipoidic as well as proteinic constituents of nutrition. We have designated it as fatty dysplasia of the pancreas because of its association with a compensatory proliferation of fatty connective tissue. Another remarkably frequent senile alteration is characterized by hemosiderinic deposits in the splenic capsule and in reticulo-endothelial elements of the spleen and liver; we refer to this change as senile mobilization of the iron mefabolism. A third group of findings in the aged implicates the internal secretory glands: we deal with benign tumoral, mostly focal proliferations in the cortex and medullary substance of adrenals, @f the thyroid gland, prostate and, sometimes, in the mammae of males which we consider to result from an enhanced activity of pituitary hormones after the climacteric decrease o r extinction of the gonadic function. We will report on all these observations in another publication, but intend to devote this present paper entirely to the most surprising finding we have made in the course of our systematic investigations on old age, namely the progressive infiltration of certain vital organs by amyloid. Haitinger and Geiser (1944), Vassar and associates (1959) as well as Hobbs and Morgan (1963),? demonstrated that amyloid deposits in spleen, liver and kidneys may be detected with particular reliability by employing fluorescence microscopy. On the other hand, after Bielschowsky a s early as 1911 had considered the possibility that senile plaques contain amyloid, on the basis of quite valid findings, Divry, since 1927 repeatedly pointed out that amyloid constitutes an essential component of both senile plaques and Alzheimer's fibrils. Although still opposed, doubted and neglected
