  What does this amount to in practice? Husserl again toyed with a variety of options, and seemed to have difficulty in reaching a settled view. According to one proposal he considered, a retention such as E* in Figure 18 does not merely represent the momentary primal impression to which it is directed, it represents (or ‘intends’) an entire act-phase or streamal cross-section. In more concrete terms, the retention in question not only contains a representation of E (the original primal impression), it also contains representations of all the retentions and protentions that were experienced with E. Since each of these nested retentions and protentions themselves represent entire act-phases, and so on ad infinitum (within the limits of the specious present) we are clearly dealing here with a highly complicated experiential structure. Thanks to this structure, later stream-phases retain a rich awareness of their immediate predecessors. But in other writings, Husserl envisages the continuity of consciousness being secured by a somewhat different mechanism: