\r,\ 



pletely inhibited. Under the influence of the rays, chloroplasts 

 change their position in the cell, as under too intense illumi- 

 nation, and they are eventually destroyed, as is embryonic tissue 

 in stems and roots. 



Results similar in kind to the above are obtained by the use 

 of radio-tellurium in a sealed glass tube. The influence here is 

 confined chiefly to the «-rays. Experiments with a rod coated 

 with poUonium, which gives off «-rays exclusively, have thus 

 far given negative results. 



Growth is retarded and may be inhibited by growing plants in 

 an atmosphere containing the radium emanation, such as may be 

 drawn from a cylinder lined with Lieber's coating. 



Photographs of the experiments, and specimens of the various 

 radio-active preparations were exhibited. The paper was the occa- 

 sion of considerable discussion. The second paper entitled "Some 

 interesting Plants from Colombia " was by Dr. H. H. Rusby. 



In view of the lateness of the hour Dr. Rusby stated that he 

 desired to reserve his paper, as planned, for some future meeting 

 when he could take the time to treat it more adequately, and for 

 the present he would show some of the more interesting speci- 

 mens and comment briefly upon them. 



The collections were made by Herbert H. Smith, who spent 

 four years collecting in the United States of Colombia near the 

 town of Santa Marta, which is about fifty miles from the coast in 

 the Sierra Nevada mountains. Although this territory was col- 

 lected over quite extensively by Karsten, whose collections are 

 at St. Petersburg and consequently not readily accessible, and 

 by \Vm. Purdy and various orchid collectors, Mr. Smith's 

 efforts disclosed many novelties. 



The total collection studied contained about 3,000 numbers, 

 embracing between 2,300 and 2,400 species, of which number 

 about fifteen per cent, are likely to prove new to science. 



The specimens exhibited were most interesting, embracing 



arborescent Violaceae, handsome twining Bignoniads and Sene- 



cios, showy Vacciniaceae, numerous anomalous Compositae, and 



many other things unfamiliar to collectors in temperate climes. 



Adjournment followed. ,- ii- ti 



•^ Edw.\kd \\ . Bekkv, 



Sirntarj'. 



