TO COLLECTORS 
I have a few fine, perfect specimens of Argonauta 
Argo (paper Nautilus), about 2% inches, at $1.00 each. 
Also a large number of rare, scarce shells. 
List submitted on application. 
J. F. POWELL, Waukegan, Ill. 
MARINE BIOLOGICAL SUPPLY DEPARTMENT 
Preserved material of all types of animals, for class 
work or for the museum. For price list 
ind all information, address 
GEO. M. GRAY, CURATOR - - WOODS HOLL, MASS. 
cii e i MICROSCOPES 
of uem: size, style and price, suited 
or all kinds of work. 
A new series of lenses 
for dissecting work have 
us which have unusually 
long working distance and 
— large flat field. These 
Less Holder for AnatomicsI Work. lenses are offered at 
prices less than any lenses of equal quality heretofore 
in use. The new Dissecting Stands are all nickeled 
metal with glass stage. 1@~ Catalog free. 
Sample copy JOURNAL OF APPLIED MICROSCOPY on request, 
BAUSCH & LOMB OPTICAL CO. 
NEW YORE OFFICE CHICAGO OFFICE: 
25th Street and Broadway, ROCHESTER, N. Y. Btate and rr tunes 
THE ONLY MACHINE | 
: E to 56 Ilinois Suse i 
recently been perfected by 
