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THE ROYAL SOCIETY OF CANADA 



It will be observed that the average life of these frogs is much 

 longer than in previous observations, while retention of nitrogen only- 

 occurred to a slight extent in two cases. The death of the sixth frog 

 was probably due to temperature fluctuations, increased temperature 

 permitting oedema. The thumb swellings were very marked in this 

 frog previous to death. 



Experiment 2. — Commenced December 15th. Four male frogs, weighing 58 

 to 60 grams, and four females, 51, 67, 68, 69 grams respectively, were immersed in 

 flowing water in a closed glass vessel, in such fashion that changes of water pressure 

 could not possibly cause entrance of air into the closed space. The initial tempera- 

 ture was 11°. It fell slowly to 4.4° on April 9th, and then slowly rose. The frogs 

 remained quiescent at the bottom of the vessel until buoyancy forced them towards 

 the surface. The results are summarized in the table. 



