Before we entirely leave the subject of edible stomachs, here's a display that I saw at the Minnesota State Fair last week. More about that later. There in the diary building was a fascinating model of a cow's stomach, with explanatory notes, and a small boy who might or might not have been trying to guess the breed. (It's clickable if you want to see more detail). I know that some early haggis recipes did indeed feature cow stomach rather than sheep. Given the size, you could have had yourself quite a feast.