42 
It is rather striking that in the St. Elizabeth cases and among the 
Connecticut males the infection foimd among patients of more than 
fifteen years' residence varies p.40 only as follows : 4.26 per cent. 5.26 
per cent. 5.SS per cent, and 7.69 per cent — figures which seem to indi- 
cate the approximate amount of endemic helminthiasis in the wards in 
question. It will furthur be noticed that at St. Elizabeth the final 
infection of the negroes (5.SS per cent is higher than that of the white 
males either at St. Elizabeth (4.26 per cent or at Connecticut (0.26 
per cent). These statistics are in harmony with the general conclu- 
sion that the worms were more common among negroes than among 
whites. It will also be noticed that the St. Elizabeth white females 
presented a higher infection 7.69 per cent than the white males at 
either St. Elizabeth (4.26 per cent or Connecticut (5.26 per cent . 
statistics which are in harmony with the general conclusion that the 
worms in question are more common among females than among 
males. 
The very high percentage 34.69 per cent found among the Con- 
necticut females is due to a certain few wards and to conditions which 
were not clear to us (see p. 58 . 
Taking a total of the cases negro women excepted . it is foimd that 
of the classes showing heavy infection (12. $6 per cent within less than 
1 year after entrance this infection has decreased in cases of 1 to 3 
years (to 9.11 per cent : also in cases of 4 to S years (3.37 per cent) and 
9 to 15 years (2.80 per cent : then it increased after 15 years to 4.42 per 
cent : classes showing a light infection (4.33 per cent) within 1 year 
after entrance have increased in 1 to 3 years to 5.36 per cent, in 4 
to 8 years to 5.51 per cent, in 9 to 15 years to 9.18 per cent, and after 
15 years to 19.09 per cent. Inserting the negro women in the last 
series, the statistics change slightly, as follows: 4.71 per cent. 6.21 per 
cent, 5.25 per cent. 9.96 per cent. 17.48 per cent. 
The general tendencies indicated by the results set forth on pages 
39-42 therefore give some plausible confirmation to the principle above 
stated, namely, that the influence of institutional life upon the preva- 
lence of intestinal worms not directly transmissible from person to 
person is to lower or raise the rate of infection among newly admitted 
inmates until it reaches a certain fairly constant amount, which the 
conditions of life in the institution will support. 
On this basis, then, the amoimt of infection foimd among patients of 
over 15 years of hospital fife represents approximately the amount 
endemic within the hospital itself, and. with one exception, this amount 
is fairly uniform among all of the above classes of patients and in the 
two institutions ; it certainly is so when compared with the wide differ- 
ence in the prevalence of intestinal worms in the different classes upon 
admission. The one exception occurs in the Connecticut women, who - 
upon admission show the intermediate rate of 8.70 per cent and after 
