An unidentified sitter

[This portrait does not appear in the Silvy daybooks. Stylistically, it ought to be in Volume 1, which covers the first nine months of 1860 — or at least in one of the first three volumes — but it doesn't seem to be there. It is presumably one of the many, non-theatrical sittings lost when all Silvy's series of theatrical portraits, taken in the spring of 1860, were excised from the first daybook sometime around the end of the century.]