Congrats to all our Facebook friends who guessed the subject of the photo! Here’s the answer from Dr. Menton.
This is a photomicrograph of the top surface of the tongue of a rabbit. The hook-like structures are called filiform papillae. These structures on the human tongue allow us to lick ice cream cones. In general the filiform papillae pull food to the back of our mouth so we can swallow it. Cows have very well developed papillae of this type, to which anyone who has been licked by a cow can attest (it can happen while you are milking them). Cows can pull grass out of ground with these hook-like papillae when grazing (their teeth are used for chewing the grass not pulling it out).