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M. Doyere's Experiments on the Bevivification of animals of 

 the types Tardigrada and Hot if era. 



Shortly after the existence of swarms of animalculae in 

 water containing organic matters had been revealed by the 

 microscope, the use of that instrument led to the discovery of 

 another fact, equally unexpected, and more difficult of com- 

 prehension, inasmuch as it still more widely differed from all 

 the results heretofore arrived at from the study of animated 

 beings. In fact, by the examination of dry dust collected from 

 a gutter, Leuwenhoeck ascertained the existence of an animal 

 which, under the influence of desiccation, ceased to move, lost 

 its form, and no longer gave any signs of life ; and which, in 

 this condition, appeared to differ in no respect from a dead 

 body, as it were mummified, by being deprived of the fluids 

 necessary for all animal existence ; and yet which, after having 

 been pi*eserved for a long period in this dried condition, was 

 restored to life by contact with a drop of water. Leuwenhoeck 

 did not perceive the whole extent of the singular fact which 

 he had thus discovered, with respect to the Rotifer of house 

 roofs, and did not pursue his researches farther on this sub- 

 ject ; but a phenomenon of this kind could not fail to excite 

 lively curiosity among zoologists, and to give rise to long con- 

 troversies, as well as to interesting experiments. It may be 

 remarked that the discovery of Leuwenhoeck soon ceased to be 

 an isolated fact in science, for Needham announced that the eels 

 of mildewed corn possessed, like the Rotifera, the faculty of re- 

 viving after having been completely dried ; and Spallanzani 

 arrived at the same result, after observation, not only of the 

 Rotifera and Anguillula, but also of another microscopic ani- 

 malcule, to which he gave the name of Tardigrade (R. tardus). 



The investigations of this skilful observer were numerous, 

 and conducted with the profoundly scientific spirit which cha- 

 racterizes all his labours, and might perhaps have been deemed 

 sufficient to convince naturalists as to the truth of the fact, 

 and to serve as a basis to subsequent inquiries. 



But the results thus obtained carried little weight, and itwould 

 be easy to give a long list of naturalists, who even at present 



