l8 /'. / TH( ">(,EMC BACTERIA. 



Three centuries later, in his disquisition upon the 

 Pythagorean philosophy, we find Ovid defending the 

 same doctrine: 1 



this sure experiment we know 

 That living creatures from corruption grow : 

 Hide in a hollow pit a slaughter'd steer, 

 Bees from his putrid bowels will appear, 

 Who, like their parents, haunt the fields and bring 

 Their honey-harvest home, and hope another spring 

 The warlike steed is multiplied, we find, 

 To wasps and hornets of the warrior kind. 

 Cut from a crab his crooked claws, and hide 

 The rest in earth, a scorpion thence will glide, 

 And shoot his sting ; his tail in circles toss'd 

 Refers the limbs his backward father lost ; 

 And worms that stretch on leaves their filmy loom 

 Crawl from their bags and butterflies become. 

 The slime begets the frog's loquacious race ; 

 Short of their feet at first, in little space, 

 With arms and legs endued, long leaps they take, 

 Raised on their hinder part, and swim the lake, 

 And waves repel ; for nature gives their kind, 

 To that intent, a length of legs behind." 



Not only was the doctrine of spontaneous generation 

 of life current among the ancients, but we find it persist- 

 ing through the Middle Ages, and descending to our own 

 generation to be an accidental but important factor in 

 the development of a new branch of science. In 1542, 

 in his treatise called DC Subtilitatc, we find Cardan as- 

 serting that water engenders fishes, and that many ani- 

 mals spring from fermentation. Van Hclmont gives 

 special instructions for the artificial production of mice, 

 and Kircher in his Mninins Subtaranciis (chapter 4l De 

 ;ermiu Rernm ") describes and actually figures cer- 

 tain animals which were produced under his own eyes 

 by the transforming influence of water on fragments of 

 from different plants. 2 



1 i hrid'l -l/ '" '.* ; !->sss, translate: U Mr. Dryden, published by Sir Samuel 

 Garth. 1794. 



1 See Tyndall : Floating Matter in tht Air. 



