THe MIcRoscopr. p har 
rests dust-tight upon another or receives accurately a piece of 
plate-glass as acover. In such a.watch-glass, covered, speci- 
mens may remain for long staining or soaking without loss of 
fluid by evaporation. 
When the concave surfaces are polished, the watch-glass is 
as clear as a lens-and becomes a perfect receptacle for transpa- 
rent dissecting material on the microscope stage. 
The solid watch-glass was first made for the use of the 
students in the Histological Laboratory, College of Medicine, 
Syracuse University, where it has proved a most satisfactory 
addition to the laboratory furniture. 
Dr. Mercer now places the dish in the market hoping it 
will prove equally satisfactory in other laboratories and in the 
hands of practical microscopists generally. 
——— ae 
GLEANINGS FROM THE ROYAL MICROSCOPICAL 
JOURNAL ON BACTERIA. 
C. H. STOWELL. 
Rie. OF PNEUMONIA.—The greater number of 
these micrococci are surrounded by a more or less broad lay- 
er resembling an envelope or capsule, colored light blue or red by 
gentian-violet or fuchsin respectively, and usually sharply de- 
fined externally. Sometimes two or three micrococci are en- 
closed in the same envelope; but they are never collected 
together into zodgloea colonies. These envelopes are soluble 
in water and dilute alkalies but insoluble in acids. The enve- 
lopes are colored by eosin, especially by weak solutions acting 
for twenty-four hours. These envelopes appear to be a highly 
characteristic peculiarity of the micrococci of pneumonia. They 
probably belong to the acme of that disease, not being found 
after the sixth day. 
BACTERIA OF THE CATTLE DISTEMPER.—The bacterium of this 
disease has been supposed to exist only in the bacillus condition. 
Lately, however, it has been found in the early stage of the 
disease in the blood and in the lymphatics and spleen, in the 
form of small round shining bodies or micrococci. 
2 
