Imperial Institute of France. 63 



We ought also to observe, that the detaUed description of 

 the family of the hydrocharidese, which M. Richard has 

 given in the course of this discussion, has a merit inde- 

 pendent of the object in dispute ; namely, that of deter- 

 mining more precisely the genera of which this family is 

 composed, and the number of which M. Richard has raised 

 to ten, because he has added five new ones to those with 

 which we were already acquainted. 



M. Lechenault de la Tour, one of the naturalists who 

 sailed with Captain Baudin, has given us some details upon 

 the trees with the juice of which the natives of Java, 

 Borneo, and Macassar poison their arrows, and which, by 

 the name of the iipas, has made so much noise. Of thesej 

 poisons there are two kinds, the upas anthiara and the upas 

 thieute. Both kill in a few minutes by the slightest punc- 

 ture, but the latter is most violent : it is extracted from the 

 root of a kind of strychnos, or nux vomica, which creeps 

 up the branches of the tallest trees. The experiments made 

 by Messrs. Delille and Majendie prove that it acts upon 

 the spinal marrow, and causes tetanus and asphixia. The 

 former oozes out from a large tree, which M. Lechenault 

 calls anthiara toxicaria, and which belongs to the family of 

 the nettles. Those who are v/ounded with an instrument, 

 poisoned in this manner, evacuate copiously green and 

 trothy matter, and die in violent convulsions. The natives 

 eat the flesh of animals which die from similar effects, after 

 merely cutting out the wounded part. 



M. Decandolle, the professor of botany at Montpelier,, 

 has promised to publish the new or little known plants of 

 the excellent garden of which he has the charge, giving 

 occasionally observations upon the genera to which these 

 plants belong ; and he has presented to the Class specimen* 

 which promise favourably of his future labours. The 

 hunJred plates which this work will contain are already 

 designed. 



Ouras3ociateM.de Bcauvois still continues his Flora 

 of Opara and Benin, of which he has this year published 

 tliel'iihand 13;h numbers. He announces for the 1-ith a 

 new division of the grasses, founded on the union or sepa- 

 ration of the aexas, and on the composition of the flower 

 and the number of its envelopes. 



Physic and Chemistry. 



Since the days of Black, it has been known that bodies 

 are not vaporized without absorbing a great quantity of heat, 

 and ihat every evaporation cools the body IVom which it 



emanates^ 



