I, ANIMALCULA OF INFUSIONS. 59 



The relation between infeds and animalcula 

 extends to the originating principles of both. In- 

 tenfe cold neither deftroys the germs of animal- 

 cula nor the eggs of infedls. The year 1709 is 

 celebrated for its rigour, and the fatal effeds it 

 had on plants and animals. The thermometer 

 fell to 1°. Who can believe, exclaims Boer- 

 haave, that the feverity of this winter did not 

 deflroy the eggs of infefts, efpecially thofe expof- 

 ed to its influence, in the open fields, on the 

 naked earth, or the branches of trees ? Yet, 

 when the fpring had temperated the air, thefc 

 eggs produced as after the mildell winters ( i ). 



1 



frozen and thawi:d feveral times, and they will ftill be as 

 lively as ever. Fifcher has feen a fpecies of taenia refift 

 freezing eight days, and the hydatis cellulofa has fur- 

 vived it as long ; Virey fur les Vers. Muller expofed a 

 glafs veflel of water containing various minute animals to 

 the cold of freezing for twenty-four hours. The ice was 

 then melted, and the bodies of the animals appeared dead 

 during twenty-four hours longer that they were examined. 

 But on the following morning he faw the Cypris pilofat a 

 fmall fhelled infeft, and the Cyclops quadricortiist which 

 is one of the monoculi, as lively as ever both males and 

 females. Some fmall water beetles alfo recovered. 

 Entoniojlraca feu InfCla tejiacea quae in aquis reperiuntur, 

 p. 5, 6.-T. 



( 1 ) Since that period, there have been winters 

 more fevere. In France, during December 1788, the ther- 

 mome'Ler fell confiderably lower, and in feveral other tem- 

 "^erate European climates. There is a memoir on the 

 fubje<5l alfo containing fome judicious remarks on thermo- 

 meters by M. GaufTen. — Memoires de la Soc'fte lifs Sciences 

 Phyfiqties de Laufanm^ torn. 3.-—T. 



