INFLUENZA. 143 
masses in the sputum. Stain in very dilute carbol- 
fuchsin for five to ten minutes, or in L6ffler’s 
methylene-blue heated to the steaming-point. 
The influenza bacteria are very small, short, with 
Fic. 77.—Bacterium influenzz: cover-glass preparation 
of sputum from a case of influenza, showing the bacteria 
within the leucocytes ; highly magnified (Pfeiffer). 
round ends, are often present in large numbers, 
and are frequently within the pus-cells. They may 
occur in pairs, and then resemble cocci. The ends 
are usually more deeply stained than the central 
portions. 
