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III. " Some Remarks on the Physiological Action of the Tang- 

 hinia venenifem." By Professors A. KOLLIKER of Wiirz- 

 burg, and E. PELIKAN of St. Petersburgh. Communicated 

 by Sir B. C. BRODIE, Bart. Received March 1, 1858. 



The famous poison-tree of Madagascar was described for the first 

 time by Aubert du Petit Thouars in his * Genera Madagascarensia,' 

 under the name of Tanghinia venenifera. At a later period, Sir W. 

 Hooker published a good description, with a figure of this tree, named 

 by him Cerbera Tanghin (see Botanical Magazine, pi. 2968), so that 

 nothing is wanted with regard to the botanical knowledge of this 

 plant. On the other hand, the physiological effects of its poisonous 

 parts have not been hitherto investigated. All we know is, that the 

 fruit of the Tanghinia is a strong poison, and is used in Madagascar 

 as an ordeal poison in the most strange and revolting way. The 

 only experiment on animals made by Ollivier, showed that 12 grains 

 kill a dog in some hours, but this experiment gave no further in- 

 sight into the real action of the Tanghinia. We hope, therefore, that 

 the Royal Society will take some interest in 'the experiments which 

 we undertook with this poison, of which the following is a short 

 abstract. 



The poison used by us was the alcoholic extract of the leaves and 

 small stems of the Tanghinia, prepared from dried specimens, which 

 Prof. Pelikan had received from Count Seyderitz of Mecklenburg. 

 About one centigram of this extract was sufficient to show the full 

 effect of the poison on frogs, when introduced into a wound of the 

 back. It acted also when given by the mouth, but in this case a 

 somewhat larger dose was required to produce a full effect. 



The observed symptoms were the following : 



1. First of all, viz. in about 5 to 15 minutes, the heart was affected 

 and stopped in its action, in such a way that the ventricle became 

 contracted and very small, whilst the auricles remained dilated, but 

 were also paralysed. 



2. The voluntary and reflex movements were at first not at all 

 affected ; but some time from half an hour to one hour after the 

 paralysis of the heart, they became weaker and weaker, and gradually 

 ceased totally without any sign of spasms or tetanus. 



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