458 The American Naturalist. ; [May, 
may be called its animal stage. In the glass jar in which it isgrowing | 
it resembles a miniature tree of many branches, flattened against the 
glass. Before it made its appearance the glass jar was so covered with 
growth of algae that one could not see through it. As soon asthe 
myxomycete made its appearance and had travelled a short distance, 
‘the glass on that part over which it passed was comparatively clear. 
Now that the myxomycete has gone several times round the jar, the 
glass is quite transparent. I took some measurements of its rate of 
progress, 
On Feb. 26, from 2.15 p. m. to 8.45 p. m. it had travelled 1} inches. 
Feb. 27, at 9 p. m. the distance covered was 63 inches. 
Feb. 28, a 9 p. m. 10} inches, 
March 1, at 9 p. m. 154 inches. 
_ So you will observe the rate of progress is not uniform, but the aver- 
age rate of progress was 5-26ths inch per hour. A curious circum- 
stance is that while the plant life disappears in all parts of the glass 
over which the myxomycete moves, it does not seem to interfere with 
the animal life on the glass. There are a large number of the brown 
Hydra and numerous small worms, which do not appear to-be affected 
in any way, although they are surrounded by the plasmodium of the 
myxomycete. 
I have not been able to definitely name the species, owing to the 
absence of the sporangium, but from figures I have seen it resembles 
Didymium serpula. Of course in the foregoing there is nothing very 
new, but having been fortunate enough to get so fine an example, r 
favorably located for examination, I thought it might interest ru , 
the members to see under the microscope, an object about which 80 
many diverse views have been held by botanists and pe 
Apparently the only reason for the botanical claim to it is the foe 
that in its reproductive stage it forms sporangia like some of the fung!, 
while on the other hand, from its first appearance in the water oF 
damp places it acts precisely like an animal in its mode of progres 
and its way of taking in and digesting solid foods. 
MISCELLANEOUS MATERIAL EXHIBITED. 
Mr. L. W. Freeman presented a mastodon’s tooth, obtained from 
Staten Island Sound by Mr. Seeley Van Pelt, while tonging for °%* 
ters. Its value was not understood by the finder, who allowed it ps 
thrown away with the refuse oyster shells, into Old Place Creek, 
whence it was recovered by Mr. Freeman. 
