636 



JONATHAN RISSER 



peculiar action was noted in the toads so tested; when the tream 

 was first directed to the nostrils, they sometimes would gasp, 

 often repeatedly, but without interrupting the respiratory act. 



The reactions of the toads in which the olfactory tl'acts had been 

 severed are well exemplified in the record of Toad No. 1 (table 2). 



The reactions of toads in which the ophthalmic branch of the 

 trigeminal nerve has been cut is shown in table 3. 



Since oil of cloves and oil of pennyroyal had given the best 

 reactions in the normal toad these substances were used after the 

 operations. As may be seen from the record above, the opera- 

 tion on the ophthalmic branch of the fifth nerve did not disturb 

 the olfactory function. 



Ether and chloroform did not affect the operated toads in any 

 manner different from the normal animals. 



After cutting the olfactory tract the animals were apparently 

 less active than toads with the ophthalmic branch severed. 



TABLE 2 

 Toad No. 1 



