i PROCEEDINGS OP THE ACADEMY OF [Biolog. 





 evaporated to dryness, and the extract thus obtained, dissolved in hot 

 alcohol. This solution, evaporated to dryness, iurnished a substance 

 similar to that obtained by the first process, but more highly colored. 



For the principle thus obtained, possessing as it does the properties of 

 an alkaloid, and in a high degree the toxic properties of the corroval, we 

 propose, in accordance with the principles of the United States Pharma- 

 copoeia, the name of corrovalia. 



Corrovalia* is, when pure a greenish-white substance, of low specific 

 gravity, and, upon the whole, similar to tannic acid in general appear- 

 ance. It is soluble in alcohol, ether and chloroform, and, contrary to the 

 statement in our original memoirs, to a slight extent in water. Heated 

 upon platinum foil, in the flame of a spirit-lamp, it is entirely volatilized. 

 With concentrated nitric acid it gives an emerald green color, which 

 deepens in tint if a small piece of bichlorate of potassa be added. 

 With sulphuric acid, a reddish-brown color is formed, which, with the 

 further addition of bichromate of potassa, changes in a few minutes to a 

 deep olive green ; with ammonia it gives a deep yellow color, but no pre- 

 cipitate ; with potassa in solution, the result is much the same ; with 

 tannic acid, it gave a white precipitate. 



With iodide of potassium in solution, corrovalia yielded no precipitate 

 or change of tint, nor did it give rise to any reaction in the presence of 

 bichloride of platinum. 



Corrovalia is uncrystallizable from all its solutions, except from that 

 in chloroform. A drop of the chloroformic solution evaporated to dry- 

 ness on a slip of glass, and subjected to microscopic examination, exhibits 

 numerous acicular crystals, mostly collected in groups, and radiating 

 from common centres. 



Corrovalia neutralizes the sulphuric chlorhydric and acetic acids, and 

 in all probability others, the quantity in our possession being too small 

 for us to investigate its properties further in this direction. The salts 

 formed with the above mentioned acids, as far as we have been able to 

 ascertain, are uncrystallizable. 



Introduced into the blood, corrovalia exerts atoxic power, equalled by 

 few if any substances hitherto known to man. A grain was dissolved 

 in one hundred minims of water. One minim of this solution killed a 

 small mouse in five minutes, when inserted under the skin, and five 

 minims in four and a half minutes produced the same result in a medium 

 sized rabbit. With frogs it is especially active. 



The amount of alkaloid obtained by us from corroval ; amounted tc 

 about ten per cent.; from vao, the proportion did not exceed four or five 

 per cent. 



Vao is therefore much weaker than corroval, its physiological actio;: 

 is very similar to the latter substance. The amount of resin contained in 

 it is considerably greater than that found in the corroval, as is also the 

 woody fibre. For the physiological effects produced by these new and 

 curious poisons, we must refer to the memoir to which we have already 

 alluded. 



Owing to the small quantity of these substances in our possessiou, we 

 have been unable to make an ultimate analysis of them, and consequent- 

 ly cannot at present give formulas of their composition. In other respects 

 we have from the same cause been unable to carry our investigations as 



*Experimental researches relative to Corroval and Vao, &c, American Journal of the 

 Medical Sciences, No Ixxv, N. S., July, 1859. 



[April, 



