A Farmer-General was a type of French tax collector whose job was to "farm" the taxes of a particular district at his discretion. Such collectors were notorious for ripping off their struggling neighbors by collecting even steeper taxes than what they were required to send to the monarch, then pocketing the difference. The Farmer-General is an extremely wealthy man described as carrying "an appropriate cane with a golden apple on top of it." The cane is appropriate in the sense that the Farmer-General is not really a farmer, but merely collects money. His harvest is made of gold.
Monseigneur made it a point to ally himself with a Farmer-General by marrying his sister to one.