196 
surface of a Stender dish cover, with a drop of saline solution. Under 
the dissecting microscope with the reflector properly adjusted, the 
hind-gut, mid-gut, Malpighian tubules and ovaries are withdrawn by 
pulling carefully on the last abdominal segment with one needle and 
holding the first abdominal segment by a corner with another needle. 
The mid-gut is separated from the hind-gut and Malpighian tubules 
as well as possible and transferred to a slide on the point of a needle, 
which should be sharp and well burnished, where it may be examined 
m saline solution, formalin, or by other methods. When the mosquito 
has been dead several hours, the mid-gut cannot be withdrawn intact 
n this event, it is generally necessary to split the chitinous abdomen 
open, and search carefully for as much of the mid-gut as may have 
e together. Zygotes can be detected with a low-power lens, 
eiss, 16 mm. objective and 8 and 12 oculars. If an absolute identifi¬ 
cation cannot be made at the time, all parts excepting the abdomen 
must e presen ce! intact, mounted with experiment number attached 
ror final identification. 
DESCRIPTION of the malarial parasite in the 
mosquito 
t of Leucocytes 
68 
20 67 crescents per 100 leucocytes. 
1 
