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DR. MAX SCHMIDT ON THE DURATION OF [Apr. 20, 



The 31st of December last has been taken as latest date for the 

 following calculation of the average lifetime of the animals in our 

 zoological garden. As the duration of life could be determined with 

 certainty for by far the greater part of the specimens, we simply dis- 

 regarded such as were entirely unsuited for calculation. Referring to 

 these latter, it should be mentioned that the difference between the 

 entire number of Rodentia and the number of specimens of the same 



