578 Proceedings of Scientific Societies. (May, 1883. 
Leidy stated that the Anodontas brought to him were infested 
with water-mites, marked with a Y-shaped yellow band; he iden- 
tified the species with the Atax ypstlophorus, described by Bonz a 
hundred years ago, as found in Anodonta cyguea of Europe. Pro- 
fessor Heilprin attacked the theory of a great ice-mountain in the 
north during the glacial era. In temperate regions clouds de- 
scend in winter to 5000 or even 3060 feet, and it is impossible for 
snow to form above the vapor line; how high this may be in the 
Arctic regions is not known, but it can scarcely be higher than 
6000 feet, which would render the filing up of ice to sucha height 
that it would flow southward over the area believed to have been 
glaciated a physical impossibility. Professor Lewis brought for- 
ward the evidence of the striz and boulders in favor of a con- 
tinuous ice flow, and stated that the ice in Greenland is now 6000 
feet thick. Professor Heilprin believed 2000 feet to be more 
nearly correct, and said that the thickness of bergs was greatly 
over-estimated, as the part under water was usually assumed to 
be equal in horizontal extent with that above, whereas, in fact, it 
was, in most cases, much greater. 
Feb. 20.—Professor Lewis read a paper by Miss Foulke des 
pe 
cribing the formation and liberation from the interior of Volvox ~ 
globator, of amceboids, which showed their animal nature by de- 
vouring the gonidea of the Volvox. These amceboids were 1i 
C i 
copper, with a laminar surface and structure caused by hammering 
Dr. J 
ment came toa fallen leaf, and immediately threw itself on 
back and pulled the leaf over its body to hide itself. 
alled attention 
e hammers of 
small beetle which had been knocked off a leaf on to 4 pave 
