We admit as many genera as there are different groups of natural species of which the fructification has the same structure.

A herbarium is better than any illustration; every botanist should make one.

No one has been a greater botanist or zoologist. No one has written more books, more correctly, more methodically, from personal experience. No one has more completely changed a whole science and started a new epoch.

The plant kingdom covers the entire earth, offering our senses great pleasure and the delights of summer.

There are some viviparous flies, which bring forth 2,000 young. These in a little time would fill the air, and like clouds intercept the rays of the sun, unless they were devoured by birds, spiders, and many other animals.

Nature's economy shall be the base for our own, for it is immutable, but ours is secondary. An economist without knowledge of nature is therefore like a physicist without knowledge of mathematics.

If you do not know the names of things, the knowledge of them is lost, too.