It seems to me the Calf's head is just clearly the most horrific ingredient. "Hashed calf's head" does sound pretty gruesome but this bit from the 1909 cookbook "Household Companion: The Model Cook Book" is no prettier:

After washing, take out the brains and put in a cool place. Tie the head in a floured cloth and boil for two hours, adding some salt to the water. Wash and carefully pick the brains, cleansing them till quite white; cover with water and stew; mash smooth, and add gradually a cup ful of the water in which the meat is boiled. Season with butter, parsley, sage, pepper and salt. Drain the head very dry, score the top and rub it over with melted butter; dredge with flour and set*in the oven to brown. When served, pour the gravy over it. Do not skin the head. Mock-turtle soup is made of calf's head, chopped fine, well seasoned and boiled, the brains being used with the yolks of eggs to make forcemeat balls.

Maybe it's the occult value or something, but I really can't think of a food less appealing to me than "calf's head." Any contenders?