NATURAL SCIENCES OF PHILADELPHIA. 



391 



Pelvette and Damourette (loc. cit.) supposed that the accelera- 

 tion of the respiratory movements was due to spinal excitation, in 

 which supposition they were undoubtedly wrong, as it was shown 

 when speaking of conia's action on the spinal cord that no excita- 

 tion occurs. As the following experiment proves that the primary 

 acceleration of the respiratory movements does not occur when 

 both pneumogastrics have previously been divided, the accelera- 

 tion is probably due to paresis of the pneumogastric centres. 



Kolliker (loc. cit.) supposed that the diminution and the sub- 

 sequent complete failure in the respiratory movements were due 

 to the action on the peripheral ends of the efferent nerves causing 

 paralysis of the muscles concerned in respiration, but as I prove 

 in the following experiments that the respiratory movements con- 

 tinue long after the occurrence of paresis, or even paralysis, his 

 explanation will have to be abandoned. 



Exp. 67. On a large frog. 3.09, injected one-quarter drop of 

 conia into the abdomen. 3.14, paresis over the whole body ; res- 

 piration continues. 3.17, the paralysis is now complete, but res- 

 piration continued until 3.22. 



Exp. 68. 5.19, injected one-half drop of conia into the abdomen 

 of a frog. 5.24, complete paralysis, but the respiratory move- 

 ments continue until 5.31. 



Exp. 69. On a young cat. 12.52, injected three drops of conia 

 into the peritoneum. 12.57, the paralysis is complete, but the 

 respirations continue until 1.20. 



