28 
Thus, the white females at the Government hospital showed a pro- 
gressive decrease in the frequency of infection as we pass from the 
yotmger to the older age groups, though the decrease was less marked 
than that foimd among the white males. 
The female negroes presented age statistics which differed radically 
from those of any other class of patients. The highest rate of infection 
occurred in the oldest group ; a rate almost as high was present in the 
second age group (15 to 30 years) : while the intermediate group (31 to 
50 years) gave a percentage about half as high as either of the other 
two groups. It is noteworthy that among both male and female 
negroes the minimum rate of infection should have occurred among 
patients from 31 to 50 years of age, while in no class of white patients 
was the minimum rate found in this age group. 
The irregularity with which the rate of infection varied in the differ- 
ent age groups among both male and female negroes and the lack of 
statistics for negroes under 15 years of age make it difficult to deduce 
from our results any conclusions with regard to the relative frequency 
of intestinal worms at different ages in the negro race; the indications 
are, however, that among negroes age is a less important factor in 
determining the prevalence of helminthiasis than it is among whites. 
Among the females at the Connecticut hospital there appeared a 
much lower rate of infection among women from 15 to 30 vears of age 
than among women above 30 years, those in the former group having 
given only 4.55 infections per 100, while the 460 women above 30 years 
old gave 86 'infections, namely, 18.70 per 100 persons. Females over 
50 years old. however, presented a lower frequency of infection than 
did the intermediate group (31 to 50 years). 
It is evident that with exception of the negro patients the seeming 
difference between males and females regarding the relative frequency 
of intestinal worms at different ages is due to the results obtained 
from the women at the Connecticut hospital. As will be seen later, 
certain female wards at that institution presented an exceedingly high 
rate of infection with whipworms, for which no entirely satisfactory 
explanation could be discovered. The women upon these wards were 
more or less advanced in years, and the high rate of infection among 
them would naturally raise the rate for females of advanced age. Our 
figures for females of different ages seem to be abnormally influenced 
by the unexplained but very striking conditions strictly localized on 
these few wards ; all other things being equal, females might be expected 
to show a relation between age and the prevalence of helminthiasis 
similar to that which appears among males. 
It must be noted, however, that the women at the Connecticut hos- 
pital had been, in part, residents of rural districts and that certain 
conditions pertaining to the rural life of males and of females, dis- 
