322 BACTERIOLOGY. 
want of sufficient hemoglobin; but if sterile rabbit, 
pigeon, or human blood be added to these media trans- 
plantation may be indefinitely performed, provided it is 
done every three or four days. Cultures may remain 
alive up to seventeen days in the ice-chest. 
The Detection of the Influenza Bacillus in Sputum. 
When it is desired to obtain cultures of the bacillus 
of influenza for diagnostic purposes from material sus- 
pected to contain this organism, it is advisable from 
the start to make use of plate cultures, the best medium 
being nutrient agar freshly smeared with rabbit’s blood. 
The sputum, blood, or other substance to be examined 
is streaked across several plates of blood-smeared agar, 
so as to leave on some considerable of the material and 
on others merely the slightest trace. An easy way to 
get blood when a large number of plates are to be made 
is to kill a rabbit and autopsy it immediately. The 
skin is turned back from the chest and the thorax 
opened aseptically. The heart is cut off at its base 
and dragged over some twenty to forty plates, as de- 
sired. The blood collecting in the thorax is used to 
smear the agar in a number of tubes, which can be kept 
in the ice-chest until needed. With a little skil] blood 
can be withdrawn aseptically from the ear vein of a 
rabbit by means of a glass tube armed with a hypo- 
dermic needle. . 
When cultures are made from sputa the endeavor 
should be made to collect the expectoration which comes 
up naturally, so as not to get any more than necessary 
of the mouth bacteria. If the mouth is at all foul, it 
should be cleansed before gathering the sputum. Cul- | 
tures should be made as soon as possible after obtaining 
the material. The plates are put in the incubator for 
