THIS note constitutes a generalization of the Zeeman comparison theorem for spectral sequences [9]. Zeeman's theorem was based on hypotheses valid for the homology spectral sequence of a fibration with simplyconnected base space; however, his hypotheses were stated purely algebraically and there was no assumption that the spectral sequence was derived from a filtered chain complex-merely that it was a first quadrant sequence and the differentials had the usual bidegrees. Thus Zeeman's version was more general than Moore's earlier comparison theorem [5]; it was also more general in that isomorphism assumptions were only made up to certain dimensions (and so only deduced up to certain dimensions).We generalize Zeeman's theorem in two directions. The most important direction is that we cover the situation of a quasi-nilpotent fibration; this is a fibrationin which all spaces are connected, and TTIB operates nilpotently on H t F, i"3=0. We say that (0.1) is strongly quasi-nilpotent if it is quasi-nilpotent and if, in addition, inB is nilpotent. Among the quasi-nilpotent fibrations we find the nilpotent fibrations [2]; these are fibrations (0.1) in which all spaces are connected and 7T]E operates nilpotently [3] on 7T ( F, i5»l. If E, B are nilpotent spaces and F is connected then F is nilpotent and (0.1) is a nilpotent fibration, and also strongly quasi-nilpotent. A special case, then, of a nilpotent fibration which is also strongly quasi-nilpotent iswhere X is nilpotent and X is the universal cover of X. We obtain a very general theorem of Whitehead type by applying our comparison theorem to the homology spectral sequence of (0.2) (see Corollary 3.4); we remark that this spectral sequence violates not only assumption (iii) of [9] but also the refinement of (iii) mentioned on p. 58 of [9]. We should mention at this point that our results strengthen those of Zeeman even when the base is simply-connected-that is, in the case Quart.