REPORTS OF MEETINGS. 
63 
utility to explain liow these changes may have originated. In 
ih.Q.Ammha we have an almost structureless mass of protoplasm 
endowed with the power of putting forth long root-like limbs, and 
potentially endowed with the power of secreting various sub- 
stances. Mr. Grenfell suggested that the first change probably 
would be the production of a race of swimming Amcehm due to 
an undulatory motion given to one of the long root-like feet. 
When this foot is reduced in thickness, and its rate of motion is 
increased, we reach the group of the Bhino -flag ell ata. The 
poww of swimming may then have led to the disuse of the root- 
feet, and to the assumption of an elongated form better adapted 
for swimming. These creatures form the lowest group of the 
true Infusoria. The evolution of the Infusoria was traced in a 
similar ’way, and Mr. Grenfell pointed out that among the highest 
forms there are distinct foreshadowings of some of the chief 
organs of the higher animals. The paper was illustrated by 
numerous diagrams. It produced considerable discussion. 
To the last ordinary meeting of the session, held on April 
5th, Mr. H . Cliarbonnier sent a notice of Ridgway’s Catalogue 
of American Birds,” which is printed in full. At the same 
meeting Dr. Ramsay read a paper on ‘AVater,” in which he dealt 
chiefly with the impurities with which it is liable to be contami- 
nated, and the means of detecting them. These points were 
illustrated by experiments and by lantern slides. 
