S. Yokogawa 
151 
Table VI. 
Position of Genital Primordium from 15 to 30 hours after Infection. 
Age of 
Body 
(length) 
Body 
(width) 
Size of 
genital 
Position of 
gen. primordium 
(distance from 
Percent, of 
distance 
from 
larvae 
(mm.) 
(mm.) 
primordium 
anterior end) 
ant. end 
Sex 
f 0-680 
0-032 
0-016 x 0-009 
0-390 
57-3 
? 
15 hours after 
0-680 
0-032 
0-014 x 0-006 
0-391 
57-5 
? 
infection 
0-702 
0-028 
0-018 x 0-01 
0-410 
58-4 
? 
0-710 
0-029 
0-015 x 0-008 
0-405 
56-3 
? 
f 0-885 
0-032 
0-016 x 0-007 
0-550 
62-1 
? 
1-030 
0-033 
0-018 x 0-007 
0-600 
58-3 
6 
0-820 
0-030 
0-021 x 0-010 
0-510 
62-2 
? 
0-780 
0-028 
0-021 x 0-010 
0-450 
57-7 
s 
24 hours after 
infection 
0-825 
0-031 
0-021 x 0-010 
0-485 
58-7 
? 
0-755 
0-030 
0-017 x 0-006 
0-490 
65-0 
? 
0-970 
0-032 
0-024x0-01 
0-750 
77-3 
$ 
0-985 
0-031 
0-028 x 0-007 
0-865 
88-0 
$ 
0-790 
0-032 
0-028 x 0-008 
0-565 
71-5 
? 
L 1-09 
0-035 
0-031 x 0-01 
0-940 
86-2 
$ 
f 0-825 
0-032 
0-017 x 0-008 
0-421 
51-6 
s 
0-800 
0-030 
0-025 x 0-01 
0-432 
54-0 
0-825 
0-031 
0-017 x 0-011 
0-463 
56-7 
•c? 
0-800 
0-036 
0-024 x 0-01 
0-437 
54-6 
30 hours after 
infection 
0-950 
0-035 
0-028 x 0-01 
0-544 
57-2 
<$ 
0-988 
0-032 
0-03 x 0-011 
0-500 
50-6 
s 
0-975 
0-036 
0-037 x 0-008 
0-876 
89-9 
$ 
0-850 
0-031 
0-028 x 0-008 
0-716 
84-2 
$ 
0-800 
0-032 
0-027 x 0-008 
0-684 
85-5 
$ 
0-900 
0-030 
0-024 x 0-006 
0-783 
87-0 
? 
of tbe male becomes more curved than that of the female, and the arrangement 
of the cells in this region is different. Comparing many specimens found in the 
lungs of the experimental rats from 15 to 23 hours after infection, I found the 
following differences in the caudal regions of the sexes (cf. Figs. 8 and 22, 
Plates IX and XI). 
1. The rectum in the male is surrounded by 10 cells excepting the cells of 
the rectal ligament and sphincter, while that of the female is surrounded by 
only five cells excepting the same cells. 
