Q 
11 
I I5X 
NH 
PROCEEDINGS 
OF THE 
A 
owa Academy of Science 
FOR 1913 
VOLUME XX 
fr>«K7^ N 
EDITED BY THE SECRETARY 
' v : i 1915 
\ 23 2 o55^y 
PUBLISHED BY THE STATE 
F>ES MOISES 
ROBERT HENDERSON, STATE PRINTER 
1913 
