^£. 





^ming to 



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'^r, the 



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resisting tk 



y so great 

 • vegetable, 



learl 



r 

 I 



ioo"C(2ifF 



le Bernard 

 y all the otki 



Tines 



of arctt' 



nperature, effl 

 estructive to 



i 



I 



ons 



i__so far as ' 



I are 



only coDW 



ertrf 



,er plants, f^^ * 

 of desic^"" 



eriods 

 long 



time in ^* 



. wi* - ^!!: 



I 



. disorr 



letely 





t:^^ beginnings of life. 



3^5 



these had been made the subjects of special and direct 

 experimentation. And^ amongst all the diversity of 

 form presented by the lowest living things^ there is so 

 much of uniformity in property — living matter^ as we 

 know it^ agrees in so many of its fundamental characters 



that biologists and chemists alike may feel a reasonable 

 assurance as to the probable universality of any such 

 rule which has been proved to hold good for a very 

 large number of organisms^ more especially when, 

 amongst this large number of cases, no exceptions 

 have been encountered. 



Practically, however, it will be found that, in order 



[iperatureof^n to appreciate the bearings of the experiments which 



we shall have to relate, it 



will be necessary for us 

 more especially to know what are the limits of vital 

 resistance to high temperatures possessed by spores of 



minoscE, very slowly ; in the case of those of Gleditchia and Labtirniitn, 

 we have found several days and even weeks necessary for the complete 

 penetration of cold water, though when the water is hot it penetrates 

 much more readily. If, therefore, the seeds are dry when immersed, and 

 are boiled for a few minutes only, they may still germinate. If they are 

 moistened beforehand, the action of boiling water has been found 

 uniformly fatal. In one of our experiments, twenty-eight seeds of 

 Gleditchia were soaked until their coverings became soft and swollen ; 

 one-half were planted at once, and the others after having been boiled 

 five minutes. None of the boiled ones germinated, while the otljers 

 did. Similar experiments with beans and with several other kinds of 

 seeds ended in a similar manner.' {Ainer . Journal of Science and Art, 

 Sept. 1867.) All the organisms in which we are interested, at present, 

 however, have no such protection. These are mere specks or masses 

 of protoplasm, which are either naked, or provided only with thin 

 coverings. 



