72 PROCEEDINGS OF THE LI]S*>'EAN SOCIETY. 



sti'ucture. Our gardener informs me that cats and dogs lick 

 whitening off glass, apparently hking the paste employed in the 

 mixtures ; it is possible, therefore, tliat gasteropods may have a 

 similar partiality. Moreover, the physiological need for carbonate 

 of lime cannot be very great in the case of a slug. 



[The panes of glass bearing the tracks have been placed in the 

 Oxford University Museum.] 



