At the end of his poem Shade mentions a dark Vanessa butterfly:

A dark Vanessa with crimson band
Wheels in the low sun, settles on the sand
And shows its ink-blue wingtips flecked with white. (ll. 993-95)

One minute before his death, as we were crossing from his demesne to mine and had begun working up between the junipers and ornamental shrubs, a Red Admirable (see note to line 270) came dizzily whirling around us like a colored flame. Once or twice before we had already noticed the same individual, at that same time, on that same spot, where the low sun finding an aperture in the foliage splashed the brown sand with a last radiance while the evening's shade covered the rest of the path. One's eyes could not follow the rapid butterfly in the sunbeams as it flashed and vanished, and flashed again, with an almost frightening imitation of conscious play which now culminated in its settling upon my delighted friend's sleeve. It took off, and we saw it next moment sporting in an ecstasy of frivolous haste around a laurel shrub, every now and then perching on a lacquered leaf and sliding down its grooved middle like a boy down the banisters on his birthday. Then the tide of the shade reached the laurels, and the magnificent, velvet-and-flame creature dissolved in it. (Kinbote’s note to Lines 993-95)

In Strong Opinions (Interview 15) VN comments on Vanessa atalanta (the Red Admirable) as follows:

Its coloring is quite splendid and I liked it very much in my youth. Great numbers of them migrated from Africa to Northern Russia, where it was called "The Butterfly of Doom" because it was especially abundant in 1881, the year Tsar Alexander II was assassinated, and the markings on the underside of its two hind wings seem to read "1881". The Red Admirable's ability to travel so far is matched by many other migratory butterflies. (p. 170)

In his novel Istoki (“The Sources,” 1950) Aldanov describes the last minutes of Tsar Alexander II and mentions the famous Dr Botkin:

В комнaту вбежaл лейб-медик, знaменитый врaч Боткин. Все перед ним рaсступились. Нaстaлa тишинa, продолжaвшaяся минуты три.

- Есть ли нaдеждa?

Боткин отрицaтельно покaчaл головой в ответ нa вопрос нaследникa.

- Никaкой, вaше высочество, - негромко скaзaл он, подумaв, что уже можно было бы скaзaть "вaше величество". (Part Fifteen, chapter XII)

In 1918 Dr Botkin’s son perished with the family of the last Russian tsar (a grandson of Alexander II).

Alexey Sklyarenko