978 
Journal of Agricultural Research 
Yol. XXX, No: 10 
which time the ovum is about 200 n 
long (fig. 2). 
The rachis disappears as the char¬ 
acter of the ovary changes to form the 
’ o-05mm 
Fig. 1 . — Ascaris lumbricoides. Germinal zone of 
ovary 
oviduct, and the ova separate from 
each other and gradually assume a 
more or less oval form. They are 
fertilized by the sperm in the receptac- 
ulum seminis, and the shell is 
developed while they are in the 
posterior end of the uterus. 
METHOD OF COUNTING EGGS 
The writer has attempted to count 
the eggs in two adult specimens of 
Ascaris lumbricoides. The genital sys¬ 
tem of the worm was carefully dissected, 
then floated in water while the many 
loops of tubules were disentangled, and 
then the uteri and ovaries were care¬ 
fully measured. After that, portions 
were cut off at different levels, mounted 
in celloidin, and cross and longitu¬ 
dinal sections made of each portion 
of tubule. After staining and mount¬ 
ing the section, the eggs were counted 
in several sections from each of the 
selected portions, and the average 
computed. In the cross sections of 
ovary and uterus (figs. 3 and 5) 
the total number of eggs present was 
counted (see columns a and a' in the 
tables); in the longitudinal sections of 
ovary and uterus (figs. 2 and 6) a 
linear count was made of the eggs 
arranged consecutively along a known 
length of the wall of the tube, and from 
that length was computed the approx¬ 
imate number in a 1 mm. length (see 
columns b and b' of the tables). By 
multiplying the number of eggs in 
cross section by the linear count for 
o-/ mm. 
Fig. 2.— Ascaris lumbricoides. Longitudinal section of ovary 
