186 The Philippine Journal of Science 1915 
in the swamp. The inhabitants are all Filipino laborers and 
their families. 
. Magbando barrio consists of only two or three houses at the 
edge of or just outside of the estate. A clear stream containing 
numerous larve of A. febrifer flows through the woods a few 
meters from the houses. Little oiling has been done in this 
region, since it is far from the center of population of the estate. 
The small population consists of Filipinos and Filipino-Mangyan 
mestizos. 
In the other barrios Anopheles rossti considerably outnumbers 
A. febrifer. Bugsanga barrio includes a long string of from 
15 to 20 buildings including some small dormitories and is 
situated on the bank of a large river, the Bugsanga. Numerous 
larvee of A. rossi and comparatively few of A. febrifer were 
found by us in this river. There is also an irrigation ditch 
entering this river in the upper part of the barrio. The popu- 
lation of the barrio is relatively small and includes both Amer- 
icans and Filipinos. This barrio is at the edge of the cultivated 
part of the estate and is about 1 kilometer from the center of 
population, so comparatively little oiling has been done in the 
river. 
The barrios of Mindoro and Lubang include the largest part 
of the population of the estate. They are situated on the banks 
of a small winding stream, Magbando River, which in places 
has swampy banks. There are numerous irrigation ditches in 
the neighborhood and small streams formed by seepage from 
these ditches. We found larve of A. febrifer in small numbers 
at the edge of this stream and some of A. rossi in the swampy 
ground. The various streams and ditches have been faithfully 
oiled, and the larve are remarkably few considering the difficulty 
of destroying them over such a large and abundantly watered 
area. Mindoro barrio has about 140 houses. Lubang has about 
75 houses including some small dormitories. The population of 
both barrios is largely Filipino with a small percentage of Japan- 
ese and a few Americans. 
Dormitory H, situated at one end of Lubang barrio, is here 
considered separately, since the conditions were somewhat dif- 
ferent from those of the other houses of the barrio. The build- 
ing, except the kitchen, is screened. It is comparatively well 
shaded and is near Magbando River on one side and a seepage 
ditch on the other, neither of which showed many larve. A 
considerable percentage of the anopheles caught in this building 
were found in the screened vestibule. On some nights this ves- 
tibule was purposely made into a mosquito trap by leaving the 
