In muscle tissue obtained from 4 pre-dynastic Egyptian mummies, the following antigens were present: mummy no. 1 AODEc, no. 2 OD, no. 3 ODC, no. 4, ODc. Result no. 1 may be due to A2 rather than to A-like substance of bacterial origin arising during burial. O and D antigens are stable even after 5000 years, which is the approx. time limit for the detection of C or c with any degree of reliability; the D antigen may well be detected after other Rh antigens have disappeared.