6 THE THEORY OF EVOLUTION 



since it apparently had ceased to act. The conclusion 

 became enforced that the petrifactions should be con- 

 sidered as remains of actual organisms which, however, 

 certainly had, in the opinion of the time, nothing to do 

 with the still existent forms of animal and plant life ; 

 they were extinct, i.e. types of life which had been 

 annihilated by the one universal flood, the Noachian 

 Deluge. 



FIG. 1. LTTSUS NATURAE. 



Obviously fancifully completed. Fig. 2 is based on a mussel 

 (Inoceramus). (After A. Kircher.) 



The most formidable upholder of this view was 

 undoubtedly J. J. Scheuchzer (1672-1733). He took 

 up arms courageously against the current ideas of 

 aerial spirits (Archaei) which bury themselves in the 

 soil and stones and so shape organic forms. * Such 

 idols/ he says in his book 'Homo diluvii testis/ f must 

 be overthrown and destroyed, not so much by subtle 

 philosophy and all sorts of brain whims, but by presen- 

 tation and observation of Nature's bodies themselves, 



