Histological preparations of the rectal mucosa from 72 rheumatic patients without gastrointestinal symptoms were quantitatively analysed. The variables recorded were the diameter (minor axis) of ten consecutive transversally cut glands, the space of lamina propria between the glands, the number of glands per high-power field, and the number of nuclei in ten consecutive areas (of lamina propria) between the glands. The digitals resulting from the sum of the values in each variable were considered characteristic of the histological state of the rectal mucosa in individual patients. In most biopsies (i.e. 99%) scores of 21 or less were recorded. The data obtained serve as a basis for comparative studies of the histological state of the rectal mucosa from patients with various chronic inflammatory conditions of the rectum.