Mr.
Galton explains the striking dissimilarity of twins which is sometimes met with by supposing that the offspring in this case divide the available gemmules between them in such a way that each is the complement of the other.

Thus, to put the case in an exaggerated way, similar twins would each have half the gemmules A, B, C,...Z., etc, whereas, in the case of dissimilar twins, one would have all the gemmules A, B, C, D,...M, and the other would have N...Z.), and am curious to learn how twins from a single ovum are distinguished from twins from two ova.

Nothing seems to me more curious than the similarity and dissimilarity of twins.
5.

Awfully difficult to understand.
6.

I have given almost the same notion.
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