FOSSIL INVERTEBRATED ANIMALS. 495 



bable that these petrifactions have a very different origin ; at 

 least, this must be the case with some, which are four or five 

 times the length of the earth-worms of our present day. 



In the possession of M. de France is a stem from Solen- 

 hoffen, which contains small asteriae, and on which a kind of 

 tube is visible, which might be taken for a portion of a fossil 

 worm, but to which bivalve shells appear to be attached in 

 many places, with their two valves striated circularly and open. 

 But there is little reason to believe that this body, any more 

 than the others above-mentioned, is a rehc of the earth-worm 

 tribe. 



The generic name of Echinus was formerly given to the dif- 

 ferent genera of the family of Echinides, which are now known 

 under the names of scutella, clypeastra, fibularia, 8fc. 8^c. 

 Those in the fossil state were called echinitis, echinometra, 

 echinodermata, ovarium, Sfc. ^c, Rumphius believed that those 

 bodies fell from the sky, as well as the belemnites, and has 

 called them bronita^ tonitru, ombrias. Nonnius imagined that 

 they were the petrified eggs of serpents. 



The Romans believed that these bodies fell upon the earth 

 with the heavy rains or thunder, or that they were the eggs of 

 toads, or petrified toads themselves. — See Pliny, lib. xxxvii. 

 and xxix. 



The authors of the fifteenth century believed every thing 

 that was said about them by Pliny. Agricola was the first 

 who rejected those fables, but he did not point out the true 

 origin of these bodies, Mercatus took them for figured stones, 

 to which nature was pleased to assign their peculiar form ; and 

 we are informed by this writer that they were formerly used in 

 enchantment. Gesner fell into the error of those who believed 

 that they fell from the sky, and was ignorant that the Judaic 

 stones, which are the points of echini, of which he has spoken, 

 had any relation with the echinites. Ferrand Imperati appears 

 to have been the first who, in the commencement of the seven- 

 teenth century, referred these stones to the echinus or sea- 



