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THE AMERICAN NATURALIST [Vol. XLIII 



the tadpoles alive. The larvae, slide, etc., were weighed, 

 and then, removing the tadpoles by means of a dissecting 

 needle, the slide, etc., were again qnickly weighed. This 

 method gave me the weight desired without killing the 

 tadpoles. There was of course some evaporation and loss 

 of water in removing the larvae. But, since it was aprox- 

 imately the same for each weight, the data are not atfected 

 to any great extent. 



This table is the average weight and measurements of 

 eighteen tadpoles which were kept in a vessel by them- 



selves with water plants. Their food was mostly dog- 

 biscuit with a little meat. 



Toads just metamorphosed were seen for the first time 

 on the morning of the twenty-third of June. During the 

 next ten days most of the toads of the early spawn aban- 

 doned the ponds. The number leaving the water at this 

 time is probably 90 per cent, of all that emerge during the 

 summer. At this time eggs and tadpoles, in all stages 

 and toads just metamorphosed could be found in the same 

 pond. Tadpoles were in the ponds as late as August 15. 

 Larvae from eggs laid April 29th were kept in the labora- 

 tory until October 20. 



^ Newly emerged toads are so susceptible to transpira- 

 tion that they must remain in damp places for a few days. 

 Many remain near the ponds in the grass, under stones, 

 etc., during the day, thereby escaping the fate of those 

 wandering away too soon. At nights or on cloudy days 

 during the time that tadpoles are transforming, the vicin- 

 ity of ponds may be alive with young toads migrating 

 from the water. 



The great numbers that leave the water or places of 



