5G THE UNIVERSE. 



which were quite calculated to mislead men's minds very 

 easily indeed. 



It is true we are, in our day, obliged to erase the charm- 

 ing romance of palingenesis, with which our forefathers 

 amused themselves. Still we must say that, although the 

 Rotiferse cannot be resuscitated when they are once dead, 

 their tenacity of life is one of the most extraordinary phe- 

 nomena. Their resistance to cold is something marvellous, 

 and we don't even know where it stops; the lowest temjjer- 

 ature that we can obtain in our laboratories does not seem 

 to have any effect upon them. I have seen these animals 

 defy a cold which would kill a man a hundred times over. 

 Rotifera^ placed in an apparatus where the temperature was 

 40° below zero Centig. ( — 40° Fahr.) issued from it full of 

 vitality. 



The natural history of the Rotiferge is a marvel from be- 

 ginning to end. I have sometimes removed them quickly 

 from the freezing apparatus and thrown them into a stove 

 heated to 80° Centig. (170° Fahr.) When they emerged 

 from this they were seen to recover their animation and 

 run about full of life. In this twofold test and formidable 

 transition from cold to heat, these Microzoa passed rapidly 

 through a change of 120° Centig. (210° Fahr.) Avithout 

 being in the least inconvenienced by it. 



An ox could not bear with impunity what imper- 

 ceptible animalcules endure.^ 



^ M. Broca remarks as follows on one of ray experiments on this extraordinary 

 vital tenacity : — "Of all tlie tests to which these revivable animals have lieen sub- 

 jected, the above is certainlj' the most astounding. Before this beautiful experi- 

 ment was performed by M. Pouchet, we had only a very indistinct idea as to the 

 power of resistance possessed by the tardigi-ades and rotifers, and it is almost in- 

 credible that, -ndieu so suddenly heated, in an instantaneous rise, indeed, of almost 

 100° Centig. (180° Fahr.), the sudden dilatation of the tissues did not produce rup- 

 ture of them. But we cannot resist the evidence, and we are bound to say that 

 M. Pouchet has discovered one of the most extraordinary properties of the rotifers 



