222 
Distribution of Hookworms 
No survey of the hookworms of North American Indians has yet been 
made. It is extremely important that this be undertaken without delay. 
Panama. 
In Panama there were two types of infection: (a) pure infections of 
N. americanus encountered among the Panamans and probably derived from 
African negro sources, ( b) mixed infections in which both A. duodenale and 
N. americanus were found. This type of infection occurred chiefly among 
West Indians who had been exposed to infection in their native islands from 
East Indian coolie sources. But it also occurred to a slight extent among 
natives of Panama who had been exposed to infection from West Indian 
negroes resident in the Canal Zone since the commencement of canal operations. 
Brazil. State of Sao Paulo. 
The species most commonly found is N. americanus but the proportion 
of Agchylostoma to Necator varies in different communities depending on 
circumstances. 
At Itatiaia, in a former coffee plantation where many African negro slaves 
were worked years ago, the ancylostome index is 1*5. 
At Rezende, which was formerly a detention and distribution centre for 
Italian, Portuguese and Spanish agricultural colonists, the ancylostome index 
as we might expect is much higher, 11*2, and is evidently due to the seeding 
of the soil with A. duodenale by Mediterranean people. 
At Brodowski the high ancylostome index of the Japanese is being markedly 
altered by residence among the native Brazilian agriculturists who are so 
heavily infested with N. americanus. 
Nothing has as yet been done to determine the species formula of the 
aborigines of South America. 
Great care must be exercised in selecting tribes who live in inaccessible 
regions unvisited by foreigners. It should not be hard to do this in the interior 
of the continent or in Andean villages. 
Europe. 
The species encountered in Europe is A. duodenale except in those immi¬ 
grants returned from Brazil or the United States. 
The hookworm found infecting Cornish miners was A. duodenale (Boycott). 
Isola (1904) examined 11,000 specimens collected by Parona from upper 
Italy and all were A. duodenale. 
Africa. 
Northern Africa. 
The species found in Egypt and Northern Africa appears to be exclusively 
A. duodenale for this was the sole species encountered in the large mass of 
material passed under review by Looss in Egypt. 
