506 Prof. W. Preyer on Anabiosis. 



scope), and keep the preparation over chloride of lime, we can 

 revive the animals after a long interval either by sprinkling 

 them with distilled water or by breathing upon them, notwith- 

 standing the fact that no metabolism has taken place in the 

 meantime. For we observe the same fragments of food in 

 the transparent stomach on the resumption of motion as at its 

 cessation *. Davaine allowed Rotifers to remain in a vacuum 

 for five days, and still was able to revive them. Doyere 

 allowed some dried specimens to remain in a " vacuum " for 

 four weeks, and saw many revive on being moistened in the 

 air. All the same the supposed vacuum must still have con- 

 tained air, for I have found that dried Rotifers, in the perfect 

 vacuum produced by Geissler's mercurial air-pump over 

 sulphuric acid, resisted all attempts at resuscitation long before 

 the expiration of the fourth week. They are no longer so 

 shrivelled as they were when they were dried, clearly because, 

 owing to the suspension of barometric pressure, the vestiges 

 of air between the wrinkles expand, so that the surface 

 becomes more or less smooth and brittle. The animals perish 

 utterly. In the open they could adapt themselves to lack of 

 food and water, to cold and heat, but lack of air was fatal. 



On the other hand, the anabiosis of Macrobioti and Rotifera, 

 and especially of certain Amoebaj and the lifeless Anguillu- 

 lina? united together by a viscid mass within a grain of wheat, 

 has been proved by the fact that they have been kept for a 

 long time in closed glasses in a dry state and at a low tempe- 

 rature without forfeiting their vitality. I have subjected 

 dried Rotifers to a very low temperature and then raised 

 them to 80°, Doyere to 153°, without destroying the whole 

 of them. 



Out of the large number of earlier observations which I 

 have collected the following in particular, concerning the 

 resuscitation of Anguillulinas, Rotifers, and Artiscoids (bear- 

 animalcules or Macrobioti), are of interest partly historic, 

 partly actual. 



Anguillulinse remain cemented together in the dried grain 

 of wheat, perfectly motionless yet capable of life, over two 

 years (Needham, 1743), for days, months, years (Buffon, 

 1748), five years (Trembley, 1750), four years (H.Baker, 

 1754), half a year (Ginanni, 1759), twenty-seven years (H. 

 Baker and Needham, 1771), for years (RofTredi, 1775), six 

 years (F. Bauer, 1823), in the weaver's thistle eight months 

 (J. Kiihn, 1858). 



* Greeff, in M. ScLultze's ' Archiv fiir mikrosk. Anatomie,' i. p. 122 

 (1865), ii. pp. 122, 320 (18G0). 



