126 



just taken, because there is nothing in its aspect to warrant the idea 

 that its means of maintaining the organic kingdoms are declining with 

 the rapidity indicated in the statements just made. 



Dr. Seller next examined Liebig's views of ammonia : — 1. As the 

 sole source of the nitrogen of plants, and thereby of animals. 2. As 

 having its exclusive origin from the interior of the earth, and never 

 from the nitrogen of the atmosphere. In regard to these statements 

 he made it appear, as there is no evidence of ammonia being thrown 

 forth from the bowels of the earth at all times, in quantity proportion- 

 ed to the waste of it necessarily sustained at the surface by decompo- 

 sition, as into uncombined hydrogen and nitrogen, that Liebig's view 

 of ammonia infers the same limitation of the existence of the organic 

 kingdoms to a few thousand years, as is deduced from the hypothesis 

 of organic matter being the food of plants. Here, therefore, he dis- 

 sented from Liebig, contending that ammonia must be produced from 

 the nitrogen of the atmosphere, and showing the probability of what 

 is taught by Professor Johnson, namely, that the nitrogen of nitrates, 

 formed from the atmosphere, is fixed by plants, as well as the nitro- 

 gen of ammonia. 



In conclusion, he reviewed the evidence of potassa, the phosphates 

 and other saline matters, of both organic kingdoms, being derived 

 originally from the crumbling of rocks ; and dwelt on the retardation 

 of vegetable physiology, by the long scepticism of botanists on this 

 head, owing, as he believed, to their distrust in the conclusions of 

 chemistry : and went on to show that chemistry must be the ground- 

 work of vegetable physiology in its present stage, and that the fre- 

 quent changes in the aspect and nomenclature of chemistry, did not 

 materially affect the facts which it daily affords for the elucidation of 

 vegetable economy. 



2. A paper by Mr. Ralfs, Penzance, on the genus Closterium. 



3. Mr. M'Nab read a continuation of his Joui-nal of a Tour through 

 part of the United States and the Canadas. The last portion read 

 before the Society gave an account of the journey from Montreal to 

 Kingston, and concluded with an account of a botanical excursion to 

 the eastward of the latter place. 



The woods to the westward of Kingston appeared very dense, 

 chiefly consisting of stately beeches, growing in rich vegetable soil. 

 Several very remarkable plants were observed, and among others the 

 Monotropa uniflora and M. Hypopitys : the former, which is abun- 

 dant in shady beech-woods throughout the country, and always grow- 

 ing from amongst leaves, is known to the inhabitants by the name of 



