398 SKETCH OF PALEOBOTANY. 



The conception of a gradual degeneration would be logically followed 

 with that of complete extinction, but, so far as we know, the latter 

 view found expression earlier than the former. Leibnitz, in the memoir 

 already cited (1706), speaks of the proofs of great physical changes tak- 

 ing place on the surface of the earth. Both Scheuchzer and Mylius 

 admitted that many kinds of living creatures may have been utterly 

 exterminated by the Flood. Jussieu proposed extinction as an alterna- 

 tive explanation. Eosinus^'''^ (1719) stated that among fossil Encrinites 

 and Belemnites there were some whose originals were unknown. Volk- 

 mann and the other theological expounders believed in diluvian exter- 

 mination, and thus explained the facts known to them that fossil trunks 

 are often found on barren islands where no trees ever grew.^^^ Walch 

 admitted very little in this fertile direction, although he regarded the 

 CalamitsB as the remains of great reeds which had no known living rep- 

 resentatives. Suckow, however, in the memoir already referred to, 

 where he was the first to recognize the affinity of the Oalamitae with 

 Equisetum, decided, after careful comparison with E. giganteum and 

 other large living species, that they probably belonged to extinct 

 species. 



The idea that the fossil remains might represent extinct species of 

 forms once indigenous to Europe now began to take shape and to work 

 a profound revolution in prevailing theories. The question then, re- 

 ferred to a few pages back, as to the time when the originals must have 

 been living, became one of paramount importance and led to the investi- 

 gation of the stratified rocks. This was the origin of true paleontolog- 

 ical research. But it could scarcely have been begun earlier. Strati- 

 graphical geology was also at the same moment in the act of being born. 

 Werner had founded his Neptunian theory, and Hutton his Plutonian, 

 while William Smith was teaching how to determine the age of rocks 

 by the fossils they contain. 



The puerile speculations about the nature of fossils which we have 

 been considering can be better excused when we remember that nothing 

 whatever was known of the earth. So long as it was supposed to be 

 only a few thousand years old, and as the only disturbance of which 

 men had ever heard was that of the Mosaic deluge, we may well 

 doubt whether the most astute of our present geologists would have 

 conceived any better explanations. In this respect the Ancients had 

 the advantage. Even Pythagoras is said to have taught that the land 

 was once under the sea. Xenophanes and Herodotus both expressed 

 this same idea, and Aristotle himself is known to have entertained 

 something like an adequate conception of time limits.'" Tertullian 

 {supra, p. 386, note 49) uttered the last faint tcho of this thought, 

 which thenceforward seems to have slumbered until the middle of 



^''^ Supra, p. 394, note 103. 



I'i's Volkmann. Silesia subterranea, p. 93. 



'»' Meteorologicorum, Lib. I, Cap. XIV, 31 ; Lib. II. 



