"The greatest pleasure in life is to be able to do what you love."

"The classification of plants is the most difficult of all tasks."

"The species and the genus are always the work of nature [i.e. specially created]; the variety mostly that of circumstance; the class and the order are the work of nature and art."

"My mind reels when, on this height, I look down on the long ages that have flowed by like waves in the sound and have left traces of the ancient world, traces so nearly obscured that they can only whi…"

"The whole of natural history depends on the accurate knowledge of species."