Laudator Temporis Acti

In Shakespeare's King Lear (3.4.131-144), Edgar in disguise is asked his name and introduces himself as follows:

Poor Tom, that eats the swimming frog, the toad, the todpole, the wall-newt and the water; that in the fury of his heart, when the foul fiend rages, eats cow-dung for sallets, swallows the old rat and the ditch-dog, drinks the green mantle of the standing pool; who is whipp'd from tithing to tithing, and stock-punish'd and imprison'd; who hath had three suits to his back, six shirts to his body,
            Horse to ride, and weapons to wear;
            But mice and rats, and such small deer,
            Have been Tom's food for seven long year.

Let's look at one dish in Poor Tom's diet, cow-dung for sallets, that is, cow-dung instead of salads. Josephus, Wars of the Jews 5.13.7 (tr. William Whiston) mentions the same dish, eaten by necessity:

Some persons were driven to that terrible distress as to search the common sewers and old dunghills of cattle, and to eat the dung which they got there; and what they of old could not endure so much as to see they now used for food.

H.L. Mencken, Happy Days: 1880-1892 (1936; rpt. New York: Knopf, 1968), pp. 135-136, claims to have eaten cow flops of another sort:

The humor of the young bourgeoisie males of Baltimore, in those days, was predominantly skatological, and there was no sign of the revolting sexual obsession that Freudians talk of. The favorite jocosities had to do with horse apples, O.E.A. wagons and small boys who lost control of their sphincters at parties or in Sunday school; when we began to spend our summers in the country my brother and I also learned the comic possibilities of cow flops. Even in the city a popular ginger-and-cocoanut cake, round in contour and selling for a cent, was called a cow flop, and little girls were supposed to avoid it, at least in the presence of boys.

I have no idea what the abbreviation O.E.A. stood for in late nineteenth century Baltimore, although I would guess the wagons carried off night soil. Mencken's cow flops remind me of another pastry with a scatological name, pets-de-nonne (in English nun's farts).

Finally, in 2 Kings 6.25 we read of the dung of another animal eaten as food:

And there was a great famine in Samaria: and, behold, they besieged it, until an ass's head was sold for fourscore pieces of silver, and the fourth part of a cab of dove's dung for five pieces of silver.

Keil ad loc. mentions an Arabic phrase meaning sparrow's dung, referring I think to saltwort, and also a German word for asafoetida, Teufelsdreck (devil's dung).

The ancient Greek word for eating dung is koprophagia. See my Latin translation of the phrase long-tongued poo eating moonbat.