Examined. 
Infected. 
Per cent. 
Oxyuris vermicularis — Continued . 
3-5 years 
61 
21 
34.43 
5-10 vears 
144 
41 
28.47 
0-15 years 
1,272 
305 
23.97 
5-15 vears . 
324 
95 
29.32 
10-15 vears 
114 
19 
16.67 
15-20 years 
113 
14 
12.39 
15-30 vears 
368 
20 
5.43 
20-30 vears 
255 
6 
2.35 
30-40 vears 
232 
13 
5.60 
30-50 years . 
371 
16 
4.31 
40-50 years 
139 
3 
2.16 
50-60 years . 
4 S 
1 
1.28 
50-70 years 
108 
3 
2.78 
50— vears 
121 
3 
2.48 
60-70 years 
30 
2 
6.66 
70-80 vears ’. 
10 
0 
0.00 
70+ vears 
13 
0 
0.00 
80+ vears 
3 
0 
0.00 
In this arrangement of the age-groups it appears that in the case of 
each of the three parasites considered a very much higher rate of 
infection occurs among persons under 15 years of age than in any group 
above that age. Where the groups are less extensive, and the persons 
less than 15 years old are divided into those under 5 years and those 
above 5 vears, a verv much higher rate of infection is found in the 
latter group, namely, in children from 5 to 15 years old : Oxyuris, how- 
ever. shows a relatively higher frequency of infection in the younger 
group, comprised of children tmder 5 years of age, than, does either 
Trichuris or Ascaris. 
The highest rates of infection with Trichuris and with Ascari-s 
appear in the two age-groups of from 5 to 10 and from 10 to 15 years, 
the rate in the former younger) group being slightly greater than that 
in the latter. Oxyuris presents its highest rate in a still younger 
group, namely, 3 to 5 years, though there is no group between 1 and 
15 years which does not show a much higher frequency with this worm 
than does any group above 15 years. 
T Ve have reports of a number of infections in infants of less than one 
year, but none is sufficiently statistical in character to be properly 
included in our tables. 
RELATION OF WHIPWORMS TO TYPHOID FEVER. 
Within recent months the point has been raised that whipworms 
may play in typhoid fever a role somewhat similar to that ascribed to 
fleas in connection with plague. With regard to this view it is inter- 
esting to compare the percentages of infection with this worm in the 
