Kallistos 7 was hypatos; owner of a seal dateable to the seventh or eighth century: Schlumberger, Sig., p. 476, no. 3 (facsimile). Obv.: invocative monogram of Θεοτόκε βοήθει with the legend τω - σω - δου - λω. Rev.: + - Καλις - τῳ υπ - ατῳ.

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