From ioo stools in which the fresh film methocl was compared 
with the plate culture and differential density method (Bass’), 
the following results were obtained: 
Strongyloides stercoralis [ij : Number of times detected in fresh 
larvae or adult 
film préparations (two coverslip 
freeliving génération. 
préparations were used) 
3 
d° 
Plate culture method (by) 
22 
Hookworm ova 
Number of times detected in fresh 
film préparations 
7 
d° 
By differential density method 
49 
Whipworm ova 
Number of times detected in fresh 
film préparations 
12 
d° 
Bv differential density method 
46 
Roundworm ova 
Number of times detected in fresh 
film préparations 
I 
d° 
By differential density method 
2 
In contrast with other tropical régions, such as the Philippi¬ 
nes, Egypt, Hong-Kong, etc., the Canal Zone does not support 
a very varied human intestinal fauna, the reason being that the 
sanitary disposai of dejecta, modem and efficient methods of dis¬ 
posai of sewage, the wearing of shoes by laborers and theenforce- 
ment of salutary sanitary régulations hâve reduced materially the 
number and grade of infections encountered. Fatal or very severe 
' cases of hookworm disease are now extremely rare, whereas during 
the first and second year of the Canal operations thev were more 
numerous. During the earl v days most of the laborers worked ba- 
refoot, and many of the townspeople of Panama, Colon, and the 
Zone villages wore rope-bottomed cloth shoes, easily favoring 
hookworm' infection. The periocl of prosperity ina-ugurated by 
the canal work, together with the natural desire of natives and 
blacks to wear fine footwear, and the improved sanitary condi¬ 
tions in which the laborers are required to live, hâve resulted in 
a greatly decreased number of hookworm infections. A few verv 
severe cases and rarely a fatal case of hookworm disease are seen 
among sonie of the natives of blacks who are living out in the 
bush, beyond the pale of sanitary measures. 
In this région the following intestinal parasites hâve been de¬ 
tected : 
Nematodes: Agchylostoma duodenale, Oxyuris vermicularis, 
(i) The differential density method yielded better results with 5 . ster¬ 
coralis than the fresh film method, but not nearly as good as by the cul¬ 
tural method. 
