The following is my translation of an article called: Kröten als Hungerkünstler von Eduard Boode. It appeared in a German popular science magazine, Kosmos Handweiser für Naturfreunde 1909, Heft 3, Seiten 87-88. I'm not aware of any previous translation.
Trevor Dykes.

Toads as escapologists from hunger by Eduard Boode

The old legends that one finds toads in stones and tree trunks which have been encased for centuries, or even millennia, but, upon their imprisonment come out alive, have recently been discussed by the London Linnaean Society at the hest of a new find of this sort. One came to the conviction that there is much truth in the old popular legend. Charles Darwin came across a hollow lump of coal with a circumference of 32cm, and this had been found on sand flats near Lewes and, when cracked open, it contained the dried out body of a dead toad. The entrance to the cavity in which the mummy lay was so tiny, that it is impossible the adult animal could have crawled in. Earlier, it was unquestionably assumed that, in such cases, the animal must have entered prior to the solidification of the stone, and the doggedness of the toad was cited. Toads are certainly determined when it comes to surviving, but it is also certain that they cannot exceed 50 years of age, and they cannot live for centuries in a cavity in coal. In the eighteenth century, the natural historian, Herrison, conducted an interesting but cruel experiment in which 3 living toads were placed in a box, and this was then encased in plaster and buried in the ground. 3 years later, on 8th April 1774, they were dug out again, cracked open and, allegedly, 2 of the 3 toads were still alive! (We provide this disputed report with all necessary caution. Brehm doubted its correctness, although he himself also cited cases when toads, in similar dungeons, held out for 18 months but then died due to suffocation.) The assembled academics in London shared the opinion of Darwin that such toads could have slipped in through an opening at a very young age, and fed themselves on smaller animals which arrived into the hollowed space via the same means. The toad grew and was eventually unable to leave. Finally, it would starve when the supply of prey ceased. Living or dead toads have been found in wooden blocks as well as in stone. The explanation here is also that the animals found their way in during their young, immature stage as they were crawling on trees, and then grew larger. As large numbers of beetles, wood lice, earwigs, millipedes and others have a lively interest in examining all kinds of crevices and openings, a toad imprisoned in this way would find prey more than rarely and, in emergencies, as has already been seen, it would take them a surprisingly long time to starve. They would, however, regret this should the small opening of their cell disappear due to the growth of the tree, meaning that it closes. Such has undoubtedly happened when one finds a dead toad in a surrounding block of wood. The toad has fallen into a natural trap, and found an appallingly slow and cruel death.

An index of more of my translations of old Kosmos articles can be found at:

Kosmos Translations Archive
kosmostranslations.htm

A number of Mesozoic (and post-Mesozoic) location summaries can be found at Localities.