Personalized headstones are the best! This one made me smile. It can be sure that this man must have loved being a member of the medical community.
The "R" on the front of his headstone could stand for the first letter of his last name, but it has been stylized as the Rx abbreviation for medical prescriptions.
On top of the headstone rests a copy of the United States Pharmacopoeia, which is essentially a book that explains ingredients and how to mix compounds to make drugs.
I wonder if he was a pharmacist, based on the trappings on his headstone...