21 
from other diseases, and, in the course of the year, many cases of 
malaria are under treatment in the wards. 
Around the Igarapes Manaos and Bittencourt, larvae of Cellia 
argyrotarsis and Ce. albimana are always to be found. During the 
period of falling river many small pools and puddles are left which 
breed numbers of these Anophelines and swarms of Ciilex fatigans 
and Mansonia titilIans. 
At very low river the upper reaches of these igarapes are 
comparatively dry, but foci of Anophelines can nearly always be 
discovered. With rising or high river the larvae of Cellia are to be 
found along the edges among the dank vegetation clothing the sides 
of these igarapes. 
Along the numerous arms of the Igarape da Cachoeirinha (Plan 
io, 15, 16) occur many breeding spots for Anophelines. The land 
in many places is low-lying and swampy for the greater part of the 
year, and only becomes dry at very low river. The breeding places 
for mosquitos are augmented very considerably by the number of 
pigs allowed to roam. These animals are always rooting about in 
the swampy land, and create numerous holes which retain water for a 
long time, and serve as favourite spots for the Anopheline ova and 
young. Along the ravines and swampy lands the inhabitants, in 
order to obtain clean water for drinking and washing purposes, sink 
small tubs and barrels into the sandy soil, and these have always 
been found to contain many imagines of malaria-conveying 
mosquitos. The occupants of the houses adjacent to the swamps 
and arms of this igarape naturally do not escape malaria, as is 
evidenced by the very large number of admissions to the Santa Casa 
and Benificente Portuguese Hospitals. During the rainy season it 
is the exception to find these people free from the parasite. On the 
eastern side (Plan 26) of the igarape the inhabitants of the houses 
along the bank and at the Colonia Oliveria Machado (Plan 24) 
exhibit signs of the ravages of malaria. 
In the North, which is the highest part of Manaos, the igarapes, 
swamps and ravines, as can be seen from the map, are rairly extensiv e. 
Villa Municipal (Plan 19) is situated in this section, and many 
Anophelines are bred in the swamps at the sides and back of the 
racecourse, near the Wireless Station. 
Around the Plano Inclinado (Plan 3) are many spots for the 
