144 HALSEY J. BAGG 
a. The first pathological condition noted was that the eyes 
became smaller, the pupils opaque, and there finally was a com- 
plete, or nearly complete, closing of the lids and total blindness. 
This condition was first observed a short time after the eyes had 
opened. The photographs in figure 11 show three views of a 
female rat about one year old with typical eye deformities. ‘The 
upper view shows the entire animal, which had grown to normal 
size and weight for its age. The left eye was nearly completely 
closed, as is shown more clearly in the lower right-hand view of 
the head at a higher magnification. Both pupils were opaque, 
but, as shown in the illustration, the right eyelids were slightly 
more opened than those of the other side. ‘The animal was one 
of a litter treated in utero on March 8, 1920, was born six days 
later, and the photograph was taken on March 1, 1921. The dose 
in this case was 2920 mc.hrs. of gamma-ray radiation, which was 
a dose higher than that usually tolerated. 
b. Mating tests showed that both the males and females were 
completely sterile in the first lots, but subsequently a first-genera- 
tion female, that had been treated with 1350 mc.hrs., mated 
with a male similarly treated, gave birth to nine apparently 
normal young. 
c. Before these adult offspring of treated animals were killed 
for histological examination, their neurological reactions were 
very carefully studied. The animals, being blind, when startled 
assumed various defensive attitudes, but save for these reactions 
their behavior was remarkably normal. There was no ataxia 
in locomotion or in any of the feeding reactions, auditory acuity 
was normal, and there was no cutaneous hypoesthesia or other 
sensory disturbances. Except for blindness, there was nothing 
to suggest abnormal sensory function. 
d. When these animals were autopsied, marked developmental 
disturbances were noted in the condition of the central nervous 
system. The cerebral hemispheres were greatly reduced in size, 
and in several cases very little cortical material remained. ‘Those 
portions of the brain that were ontogenetically older (the archio- 
striatum and the cerebellum) were apparently normal. The 
optic tracts were markedly atrophic. Correlated with this 
