as observed in the Tongue of the living Fkqg\^f^,^j^^ 



prosecute it in common. My surprise therefi!WSe?tjjB5»great, 

 when a few days after I was informed (without any intimation 

 from M. Donn£) that he had communicated the experiment 

 to the Societe Philomatique. At the next meeting of the 

 Society I attended, and found that in the proces verbal of the 

 preceding meeting, in giving an account of the experiment, 

 M. Donne had omitted to mention rny name and co-operation. 

 I seized the opportunity to rectify this mistake, and to state 

 the arrangement that I had made with M. Donne, and to 

 disclaim any precedence on his part. I have only to add, 

 that these statements were made before a very full meeting of 

 the members, that M. Donne was present, and that they were 

 received by him without contradiction. I should not have 

 deemed it necessary to enter into these details if I had not 

 seen at page 108 of his Cows de Microscopie an account of 

 these observations almost literally the same as inserted in 

 the minutes of the Societe Philomatique, with the following 

 slight comment: — " Voici comment se prepare cette belle 

 experience dont l'idee premiere m'a ete donne par un 6\e\e 

 etranger, qui suivait mes cours, M. Waller." 



To prepare the animal for the experiment, it must be rolled 

 up in a strip of linen, leaving the head and the extremities of 

 the legs uncovered. Arranged in this kind of swaddling band- 

 age with a little care, it is incapacitated from making any 

 violent movement, which is indispensable for the success of 

 the experiment, while at the same time it is perfectly able to 

 breathe. We must next provide a slip of sheet-cork rather 

 longer than the frog : at one extremity a circular piece about 



the size of a shilling is to be cut out, so as to form an open- 

 ing to allow of the passage of light when the tongue has been 

 stretched over the opening. The frog is now to be placed 

 on the slip of cork, where it may be secured by a few turns 



