S. T. Darling 225 
preted as meaning that the older worms die and are expelled, while there is 
no re-infestation or new infestation to make up this loss. 
The people living in the kampongs round about outside the prison have, 
as we have seen, an ancylostome index of 0-88 %. 
Within the jail compound the index is 9-2 % from a total count of 8638 
worms derived from 118 prisoners. This indicates that the prisoners bring 
their hookworms in with them and do not derive them directly or indirectly 
from the kampong people outside the jail through polluted water or food. 
We are confirmed in this view on an analysis of the findings, after separating the 
men into groups based on the part of the Netherlands Indies they came from. 
Thus there were two prisoners giving their place of origin as Batavia or 
the Preanger, that is, West Java. The total worm count was 130 and the 
ancylostome index was 0*76 which is a West Java index. 
There were nine prisoners from mid or East Java. The total worm count 
was 755 with an ancylostome index of 7*5 %—a mid-Java index. 
Taking up the prisoners from Sumatra and other islands of the Netherlands 
Indies the index of each place may be ascertained from the prisoners and their 
respective differences noted. 
Madura. This small island almost touches the eastern end of Java. There 
were 16 Madurese prisoners from whom 1263 hookworms were obtained; the 
ancylostome index was 13-7 %. 
Bali. This interesting island, where the Hindu religious influence is still 
paramount, yielded five prisoners; the worm count was 348 and the ancy¬ 
lostome index 4*0 %. 
Lombok , a neighbouring island, with 4 prisoners and a total worm count 
of 479, gave an ancylostome index of 3-3 %. 
Timor. This island, with four prisoners and a worm count of 100, gave 
an ancylostome index of 62-0 %. 
Sumatra supplied 12 prisoners. The total worm count was 919 of which 
only 7 worms were A. duodenale, the ancylostome index being 0-9 %. Thus 
the index of Sumatra resembles that of the people of the adjoining portion 
of West Java and the Malay Peninsula in contra-distinction to that of the 
people of mid and East Java and the chain of islands extending towards 
Timor. 
(There were two prisoners who had worm formulas resembling that of the 
Chinese. One of these, a Madras Tamil, had lived five years close to Chinese 
lines. The ancylostome index of these two men (38 worms) was 65 %. It is 
evident that they were infested from Chinese sources.) 
Celebes. This island lies to the north of. Timor and to the west of Borneo. 
It supplied four prisoners yielding 523 hookworms, all N. americanus, the 
ancylostome index therefore being nil and representing what we may call the 
primitive Malay species formula. 
This completes the data, highly interesting and important as they are in 
respect to the indices of the autochthonous population of Indonesia. 
15—2 
