14 British Asscciation for the Advancement of Science. 



grew probably as well as they would have done in a green-house 

 or hot-house. They were all foreign, and some of them requir- 

 ing a great heat. Several had ripened seed. 



Mr. Gray stated, that he had grown Droseras under glass jars ; 

 one circumstance with regard to them he thought worthy of re- 

 mark, their leaves did not turn red, as is usual when exposed to 

 the atmosphere. Prof. Graham observed, that although in Mr. 

 Ward's experiments atmospheric air had been admitted, he did 

 not think it essential to the welfare of the plant. Plants grown 

 in this manner only required a glass large enough to contain a 

 sufficient quantity of air, to permit of the absorption of oxygen 

 without deteriorating the air of the vessel to such an extent as to 

 injure the plant. The want of red in the leaves of Drosera, he 

 thought, depended on the presence of moistm'e. A singular point 

 was, that plants growing naturally in arid soils and climates, flour- 

 ished in the humid and confined atmosphere of the closed jars. 

 He had placed under jars completely closed some plants of Cacti, 

 which had floiu'ished more than those not so situated. He did 

 not think that animals could be sustained in the same manner, as 

 they consmiied all the oxygen which they inspired. — Dr. Tra- 

 vers remarked, that he had seen common mould, which was a 

 species of fungus, in a tube which had been heated and hermeti- 

 cally sealed for two years. — Mr. Bowman had observed at the 

 Duke of Devonshire's, Chatsworth, that Droseras did not mider 

 the jars change the color of their leaves as in open air. He 

 wished to know of Dr. Graham, how long his Cacti had lived in 

 a moist atmosphere ; they were naturally at certain seasons of the 

 year exposed to heavy rains. He thought it was very possible 

 for plants and animals to hve together. — Mr. Dmican inquired if 

 plants were healthy, and fit to be transplanted to the open air 

 when treated in this manner. — Professor Graham stated, that the 

 Cacti had lived without access to air eighteen months. He 

 believed that plants and animals might live together, provided 

 the vessel in which they were inclosed was sufficiently large to 

 enable the plants to absorb the carbonic acid gas expired by the 

 animals. This would be a representation in miniature of what 

 takes place in our own world. — Prof Lindley, in reply to Mr. 

 Bowman's question, stated, that plants suflered little when con- 

 fined in carefully closed vessels. From improper treatment they 

 may become debilitated, but he had seen them arrive from for- 



