French National Institute. 369 



which modifies the ideas entertained upon the causes of the 

 ascension of the sap. 



To descriptive botany belong his history of the oily plants, 

 of the Utiacece, of the astragal, the edition of his French 

 Flora, which he published under the eye of our colleague 

 M. de la Marck, and- various mcmo'irs on particular sub- 

 jects ; works which have enriched the catalogue of vegeta- 

 bles with 37 genera, and more than 300 species formerly 

 unknown. 



Lastlv, in the materia medica he was the first to distin- 

 guish the various vegetables confounded under the name of 

 ipecacuanha, and those which are jumbled together under 

 the name of Corsican moss; and in a treatise upon the agree- 

 ment of the virtues of plants u'ith their natural families, he 

 has developed, according to new views, the rales to be fol- 

 lowed in these sorts of inquiries; rules, the neglect of which 

 has led into serious errors those who were occupied before 

 him with this subject, one of the most important of prac- 

 tical botanv. 



To all these labours M. de Caadoile has added three me- 

 moirs, wliich he j)resented to the class in the course of the 

 last half year. 



The first is on the subject of the parasite mudirooms, 

 which are developed under the epidermis of vegetables, and 

 whicii cause fatal diseases to several useful plants : the nisi 

 or char, which destroys corn, and the caries or rot, which 

 poisons wheat, are probably to be ascribed to this cause. It 

 has been hitherto supposed that these nmshrooms were in- 

 troduced by the pores of the epidermis; but as coloured li- 

 quors cannot pass through these pores without great diflfi- 

 culty, and as a simple application does not inoculate these 

 diseases upon the plant, M. de Candolle thinks that their 

 germs are introduced by the roots with the nutritive juices 

 of vegetables, and circulate in the interior of the vessels, 

 until they arrive at the places proper for their development; 

 he compares them in this respect to intestinal worms, which 

 cannot subsist except in the interior of the body ot other 

 animals: from this theory, and from the observation that 

 tach spcci s of parasite mushroom can only propagate itself 



V^jI. 28. No. 112. Sept. 1807. A a 'ia 



