102 



Selections. 



[NO. 7, NEW SERIES. 



ence to the irritability of the muscles and nerves, on the contrary, 

 it is easy to show that the ligature or excision of the heart has not 

 the same influence as the Antiar, inasmuch, as in the first case the 

 muscles and nerves are found irritable six or seven hours, and 

 more after the experiment has been made. Therefore it may bo 

 said that the Antiar has a direct action on these organs. 



These points once demonstrated, there remained one more ques- 

 tion to elucidate, namely, whether the Antiar acts only upon the 

 muscles, or also upon the nerves. If we consider that the Antiar 

 undoubtedly paralyses the muscles, we may easily see that the loss 

 of the excitability of the nerves possibly depends merely upon the 

 impairment of the muscular contractility, and is therefore not real, 

 but only apparent. With a view to determine the real state of 

 things, I tried a third series of experiments, poisoning frogs in 

 such a manner that the muscles of one limb were kept free from 

 the influence of the poison. This was done in two ways, first, by 

 putting a ligature round the crural artery and vein of one leg, and 

 secondly, by cutting through a leg entirely, after the ligature of 

 its vessels, with the exception only of the ischiatic nerve. In 

 poisoning frogs treated in one of these ways, through a wound of 

 the back, I found that, with the exception of the heart, the Antiar 

 acts in the first instance upon the muscles. This isjshown by the 

 fact, that in the second hour, at the time when the muscles of the 

 poisoned parts have lost their irritability, the nerves of the sacral 

 plexus in the abdomen still possess their full influence upon the 

 muscles of the leg which has been kept free from the action of the 

 poison. One might be inclined from this to conclude, that the 

 nerves are not at all acted upon by the Antiar, but this inference 

 would be erroneous. In fact, the experiments just mentioned, if 

 followed a little longer, show that in the third or fourth hour the 

 sacral plexus also becomes inactive, at a time when the muscles of 

 the non-poisoned leg are fully contractile. The Antiar, therefore, 

 paralyses also the nervous trunks, but later than the muscles. 



From all the experiments, it seems to follow that the Antiar is 

 a poison which acts principally upon the muscular system (the 

 heart and the voluntary muscles), a conclusion in favour of which 



