xiv LETTERS TO MARCO 93 



this, no doubt to lighten themselves for 

 jumping. 



Shakespeare, as usual, is right in describ- 

 ing the 



Toad, that under the cold stone, 

 Days and nights hast thirty-one 

 Sweltered venom sleeping got, 



as toads do swelter venom, and can easily 

 exist thirty-one days beneath stones without 

 food; but the old and oft-repeated idea that 

 they could exist in perfect seclusion for almost 

 an indefinite period was set at rest long ago 

 by Dr. Buckland. He prepared a number 

 of stones of different sorts and had small 

 cavities made in them, in which toads, after 

 having been weighed, were placed ; they were 

 closed up with glass, cemented down, and 

 then buried ; at the end of a year a few 

 were still alive, and in one or two instances 

 where the cementing had been insecurely 

 done they had actually increased in weight, 

 having no doubt partaken of sundry small 

 insects which had penetrated into their 



