And I thought this one would be easy.
It’s obviously a composite image — if the cut-off tails of the canary and the great tit weren’t sign enough, the fact that the plate is named in English and the birds in German should tip us off. But googling didn’t get me anywhere, so it was time to start rummaging.
I recognized the ultimate source of the great tit as one of the loveliest of the national avifaunas produced in the early nineteenth century, Johann Conrad Susemihl’s Teutsche Ornithologie, published in Darmstadt in 1811.
After a long series of bad guesses, I got lucky with the canary, the ancestor — an ancestor — of which I stumbled across in the Abbildungen to Lorenz Oken’s Allgemeine Naturgeschichte.
And luckier when I noticed that that figure was numbered 7, just as the bird on the calendar page. Wonder what number 1 on the plate might be….
Aha. A great tit, obviously copied (at whatever remove) from Susemihl, but differing from the figure in the Teutsche Ornithologie in the same ways as the image on my calendar.
The trail just got a lot warmer, but who extracted those two birds and plopped them down among all those eggshells? And who — if not the same plagiarist — lifted the plate to use in an English-language oology?
Amazon, of all things, turns out to be selling replicas of a related image:
The differences are obvious, not least among them that my calendar replaces the nest next to the canary with that next to the great tit, removing the foliage to help it fit better. Unfortunately, Amazon, that great paragon of scholarly acribie, fails to cite its source.
Dead end. But surely somebody out there knows, and somebody can help me trace my calendar page back to the Teutsche Ornithologie. Fun stuff.