NATURAL SCIENCES OF PHILADELPHIA. 



389 



As no increase occurred after the pneurnogastrics were cut, the 

 increase in the number of pulsations in the other experiments must 

 have been due to a depressing action on the pneumogastric centres. 

 The subsequent diminution in the number of pulsations can readily 

 be explained by the occurrence of paresis of the vaso-motor nerves, 

 this latter being due to commencing paralysis of the cord. 



Arterial Pressure. Conia causes the column of mercury in the 

 cardiometer to be decidedly lowered at first, but very soon the 

 mercury again rises to far above its original height. The follow- 

 ing experiment illustrates this: 



Exp. 59. On a large cat. Normal pressure, 7^ to 8 cent. met. 

 2.07, injected one drop of conia into the femoral vein. 2.08, arte- 

 rial pressure, 1 to H. 2.09, arterial pressure, 8 to 8^. 2.10, pres- 

 sure, 8J to 9. 2.11, pressure, 10 to 11. 



Action on the Respiratory System. The first effect of a poison- 

 ous dose of conia is to cause an increase in the number of respira- 

 tory movements; this is followed, sooner. or later, by a diminution, 

 and ultimately, if the dose be sufficiently large, by their complete 

 cessation. 



