64 SELECTIONS FROM HUXLEY 



be obtained, that that deposit was formed in the sea. Now 

 the remains of animals of all the kinds which have been enu- 

 merated, occur in the chalk, in greater or less abundance; 

 while not one of those forms of shell-fish which are character- 

 5 istic of fresh water has yet been observed in it. 



When we consider that the remains of more than three 

 thousand distinct species of aquatic animals have been dis- 

 covered among the fossils of the chalk, that the great major- 

 ity of them are of such forms as are now met with only in the 



10 sea, and that there is no reason to believe that any one of 

 them inhabited fresh water the collateral evidence that 

 the chalk represents an ancient sea-bottom acquires as great 

 force as the proof derived from the nature of the chalk itself. 

 I think you will now allow that I did not overstate my case 



15 when I asserted that we have as strong grounds for believing 

 that all the vast area of dry land, at present occupied by the 

 chalk, was once at the bottom of the sea, as we have for any 

 matter of history whatever; while there is no justification 

 for any other belief. 



20 No less certain it is that the time during which the coun- 

 tries we now call southeast England, France, Germany, 

 Poland, Russia, Egypt, Arabia, Syria, were more or less com- 

 pletely covered by a deep sea, was of considerable duration. 

 We have already seen that the chalk is, in places, more 



25 than a thousand feet thick. I think you will agree with me, 

 that it must have taken some time for the skeletons of animal- 

 cules of a hundredth of an inch in diameter to heap up such 

 a mass as that. I have said that throughout the thickness 

 of the chalk the remains of other animals are scattered. 



30 These remains are often in the most exquisite state of preser- 

 vation. The valves of the shell -fishes are commonly adher- 

 ent ; the long spines of some of the sea-urchins, which would 

 be detached by the smallest jar, often remain in their places. 

 In a word, it is certain that these animals have lived and died 



