This may be the second most impressive Turducken variation I've ever heard about. The first? From the Wikipedia page itself:
In his 1807 Almanach des Gourmands, gastronomist Grimod de La Reynière presents his rôti sans pareil ("roast without equal"): a bustard stuffed with a turkey, a goose, a pheasant, a chicken, a duck, a guinea fowl, a teal, a woodcock, a partridge, a plover, a lapwing, a quail, a thrush, a lark, an ortolan bunting and a garden warbler. The final bird is very small but large enough to hold just an olive; it also suggests that, unlike modern multi-bird roasts, there was no stuffing or other packing placed in between the birds. It appears to be illegal to make today as some of the species are endangered.