It is my object, in the following work, to travel over ground which has as yet been little explored and to make my reader acquainted with a species of Remains, which, though absolutely necessary for understanding the history of the globe, have been hitherto almost uniformly neglected.

Hence the same instant which killed the animals froze the country where they lived. This event was sudden, instantaneous, without any gradual development.

But the revolutions and changes which are responsible for the present state of the earth are not limited to the upsetting of the ancient strata and to the ebbing of the sea after the formations of new layers.

Nurse, it was I who discovered that leeches have red blood.[]On his deathbed when the nurse came to apply leeches

The observer listens to nature: the experimenter questions and forces her to reveal herself.

It is evident that one cannot say anything demonstrable about the problem before having resolved these preliminary questions, and yet we hardly possess the necessary information to solve some of them

Secondly, the nature of the revolutions which have altered the surface of the earth must have had a more decisive effect on the terrestrial quadrupeds than on the marine animals.