39 
the great prevalence of parasites among the men admitted from the 
Army. Among the females at the Government hospital and among 
both males and females at the Connecticut hospital the frequency is 
comparatively low upon admission, these patients being admitted 
almost entirely from civil life. 
In this connection we have prepared Table 1, showing the apparent 
influence of institutional life when the frequency of whipworms is high 
in newly admitted patients (army men and male negroes admitted to 
the Government hospital) and when it is low (Connecticut patients 
and women admitted to the Government hospital). 
By considering Trichuris alone in this comparison we make the test 
not only simpler but more exact also, as the number of infections with 
the other worms (except Oxyuris) is too few to form satisfactory 
grounds for study in this relation. 
Among the white and negro males at the Government hospital, the 
two classes showing the highest initial percentage of infection (12.67 
and 13.79 per cent), the rate tends to decrease as the duration of 
institutional life of the patients advances. 
Among the white women at St. Elizabeth’s and both males and 
females at the Connecticut hospital, with a prevalence of 3, 3.23, 
and 8.70 per cent of infection upon admission, there appears to be a 
general tendency to an increase in the rate of infection among the 
patients of longer residence in the hospital. 
In no case, however, is there a consistent variation in the rate of 
infection throughout all the groups. Among the negro women the 
figures vary so erratically that they do not seem to conform to any 
possible rule. Among the white males the rate, after consistently 
falling from 12.67 per cent in the first group of less than one year’s 
residence to 1.61 per cent among the patients of from nine to fifteen 
years’ residence, rises to 4.26 per cent in the last group (of those who 
had been in the hospital over fifteen years). The male negroes, after 
dropping from 13.79 in the first group to 10.17 in the second, maintain 
practically the same rate throughout the remaining groups until reach- 
ing the last (of over fifteen years of hospital life), where the infection 
drops to 5.88 per cent. 
Among the classes of patients who come to the hospital with a rela- 
tively low degree of infection the white women at St. Elizabeth’s present 
a uniformly increasing rate from 3 per cent, among those recently 
admitted, to 7.69 per cent among those admitted fifteen years or more 
prior to examination, with the exception that among the 66 women 
who had been in the hospital from four to eight years no infections 
appear. The Connecticut males show 3.23 per cent of infection upon 
admission, 4.38 per cent in the next group, of from one to three years’ 
residence, 2.27 and 3.70 per cent, respectively, in the two succeeding 
groups, and reach 5.26 per cent, their highest rate, among those of 
