Modern science suggests another possible source of these distinct spectra of memory. May it not happen that, by the law of hereditary transmission, which is now being applied to mental as well as bodily phenomena, ancestral experiences will now and then reflect themselves in our mental life, and so give rise to apparently personal recollections? No one can say that this is not so. When the infant first steadies his eyes on a human face, it may, for aught we know, experience a feeling akin to that described above, when through a survival of dream-fancy we take some new scene to be already familiar. At the age when new emotions rapidly develop themselves, when our hearts are full of wild romantic aspirations, do there not seem to blend with the eager passion of the time deep resonances of a vast and mysterious past, and may not this feeling be a sort of reminiscence of prenatal, that is, ancestral experience? This idea is certainly a fascinating one, worthy to be a new scientific support for the beautiful thought of Plato and of Wordsworth. But in our present state of knowledge, any reasoning on this supposition would probably appear too fanciful. Some day we may find out how much ancestral experience is capable of bequeathing in this way, whether simply shadowy, undefinable mental tendencies, or something like definite concrete ideas. If, for example, it were found that a child that was descended from a line of seafaring ancestors, and that had never itself seen or heard of the "dark-gleaming sea," manifested a feeling of recognition when first beholding it, we might be pretty sure that such a thing as recollection of prenatal events does take place. But till we have such facts, it seems better to refer the "shadowy recollections" to sources which fall within the individual's own experience. We may now pass to those hallucinations of memory which are analogous to the _centrally_ excited hallucinations of sense-perception. As I have observed, these are necessarily vague and imperfectly developed.