and its Alkaloid Conia. 411 



sating vigorously. A drop of conia allowed to fall on the right auricle, at once 

 stopped its action, and rendered it no longer irritable, even under galvanism ; and 

 the same effect was produced, though less quickly, on the right ventricle. In 

 nineteen minutes, while the vermicular movement of the intestines was vigorous, 

 a loop was pulled aside, and touched with conia ; upon which it instantly contracted 

 with force, and the vermicular action was no longer continued through that por- 

 tion, but was arrested on approaching it ; nor was this part irritable under galvanism. 

 This experiment was repeated on various portions of intestine, and invariably with 

 the same effects. In twenty-three minutes the muscles on the inside of both thighs 

 were laid bare, and several drops of conia were spread over those of one leg. In a 

 few seconds galvanism, which previously excited vigorous contraction in the muscles 

 of both sides, caused much less in the poisoned limb than in the other ; and this 

 difference quickly increased, till the contractility was all but extinct in the former, 

 while it remained tolerably entire in the latter. 



Exp. VI. The preceding experiments, on the direct action of conia on muscular 

 contractility, were repeated on the muscles of a frog. The hind legs were severed 

 from the body, and then from one another, and skinned. In the intervals between 

 the experiments, the limbs were covered with the detached skin to preserve the ex- 

 ternal muscles from drying. One limb was not otherwise treated ; but the other 

 had conia carefully spread over the whole exposed muscles, — in the state, howevei - , 

 of neutralization with muriatic acid, in order to get rid of the effects possibly arising 

 from the direct irritant action of conia itself. In forty-five minutes, when the crural 

 nerve of the limb not touched with the solution, was galvanized, powerful contraction 

 was excited in all the muscles ; but in the poisoned limb the thigh alone moved, and 

 that much less than the other. In sixty minutes the contractions in the thigh of the 

 poisoned limb were very faint, while in the other the whole limb was powerfully con- 

 tracted. In seventy-five minutes contractions were excited very feebly in the poi- 

 soned limb, and only when the galvanic circle was interrupted ; while, in the other, 

 they were nearly as strong as ever. Next morning, twenty-one hours from the be- 

 ginning of the experiment, the femoral muscles of the unpoisoned limb contracted 

 obviously when a galvanic current was transmitted to them from the femoi'al nerve, 

 but not when both poles were applied to the nerve. In the poisoned limb, no trace 

 of movement could be elicited in any manner. 



The facts in this and the two preceding experiments show, 

 that conia and its muriate produce exhaustion of muscular con- 

 tractility wherever they are directly applied ; although this pro- 

 perty of muscular fibre seems wholly unaffected by the indirect 

 action of the poison. It is not unworthy of remark, that, in the 

 tenth experiment, muriate of conia seemed to have no direct ex- 

 hausting effect on the contractility of the heart. 



VOL. XIII. PART II. 3 G 



