Explain Slocum's experience with a botanist. What was special about the interaction?

While Slocum was on Mauritius, he was visited by a botanist. The botanist named a new flower he had discovered after the captain. Slocum writes that he was both honored and amazed. Slocum had known someone in Boston who had paid $30,000 to have a flower named after his wife. Slocum had paid nothing for the honor and his flower was much larger!