THE ANIMAL KINGDOM. 49 



esis has faded before exact experiment, we must admit that 

 the Rotifera possess an extraordinary and almost prodig- 

 ious vital power of resistance. In mould which has been 

 kept two or three years, they can be seen lengthening and 

 recovering animation when they are placed in contact with 

 a few drops of water. 



Many other animals exhibit a vitality not less remarkable 

 than that of the Rotifera. However, as they are too large 

 to impose upon us in this way, it is not averred that they 

 resuscitate, but that they can go several years without eat- 

 ing. Sundry molluscs of the snail tribe hold this position, 

 owing to the facility with which they bury and shelter 

 themselves in their shells. 



Pupae, left forgotten in a box, have remained there four 

 years, clinging to the walls in all the immobility of death, 

 and have been released from their torpor and recalled to 

 life by giving them a little nourishment. But the resurrec- 



ries in order to verify the exactness of our assertions. Every time they conducted 

 the experiments with the precision which we first introduced into science, it was 

 found that not one animalcule could be revived. It is true that in one experiment 

 the members of this society succeeded in bringing a few rotifers to life again, 

 after having exposed them for several minutes to a temperature of 212 Fahr., a 

 temperature which had been regarded as sufficient to produce complete desicca- 

 tion of these animalcules. But in this solitary case they only attained this result 

 by violating the rigorous mode of experiment which I look upon as an indispensa- 

 ble element, for they caused a sudden rise in the thermometer of 72 Fahr. 



The charge I make against M. Broca, the learned author of a report on this 

 subject, is that of not having plainly said, as he ought to have done, that the tar- 

 digrades, which he never saw resist a heat of 212 Fahr., and the Anguillulae, 

 which perish at a much lower temperature, ought to be struck out of the list of 

 animals which can be resuscitated. The rotifers do not resist a temperature of 

 212 Fahr. any better when the experiment is conducted in such a way that they 

 are really subjected to this heat. 

 4 



