YELLOW FEVER EXPEDITION 
537 
The adult insect as seen in ' bred ' specimens is very sleepy during the daytime, 
it sits on surfaces in the ' correct ' attitude, the abdomen being inclined at an angle 
of about 45 0 to the vertical. The hind legs and tarsi are generally kept close together, 
contrasting with the widely separated hind legs of the 'culices.' In two houses (one 
on the Est Nazareth and the other on the B. campos) adults were seen on the wing 
after dark, about 7.30 p.m. To my knowledge, I was only bitten by Anopheles on 
two occasions, once about an hour before sunset (about 5 p.m.), and again about an 
hour after sunrise (about 7 a.m.) ; there was no untoward effect. This is simply 
noted as evidence that this species may bite during daylight, at any rate at the 
beginning and close of the day. 
By local repute there is much malaria at Para ; but out of the Englishmen and 
other foreigners that I met living in different parts of the city there was only one 
who had definite ague attacks, and he was in the habit of going out on expeditions, 
and did not trouble about taking a mosquiteiro. The fringe of the city bordering 
on the swampy low-lying regions are responsible for most of the cases. By reputa- 
tion the more out-lying district, where the huts are right in the swamp, are bad 
for ague, but in general the dwellers, who were questioned in these parts, where the 
huts are some distance apart, denied that they had fever, and dredging and inspection 
of the overflowed ground failed to yield any Anopheles larvae. 
Blood examination of cases about the city generally shewed tertian parasites ; 
one case of quartan was seen. Crescents and so-called aestivo-autumnal parasites were 
more common amongst the cases coming from the islands ; these persons were often 
in a most dreadful condition of extreme anaemia, their appearance quite waxy and 
almost translucent, their blood extremely watery, and shewing marked alterations 
of their few red blood corpuscles (macrocytes, microcytes, poikilocytes, and nucleated 
reds). 
Positive diagnosis of ague by blood examination is by no means easy in the 
semi-civilized population of Para. This, I think, is attributable to the wholesale 
faith in and use of ' Remedios,' and a case of illness of any kind which has not had 
quinine in some form or other is a rarity. The importance of distinguishing mild 
cases of yellow fever from ague was not appreciated, and notwithstanding oft- 
repeated requests to withhold quinine, often even in cases in which there 
did not appear to be any indication far less any necessity for the drug, 5 * we 
generally had to be content with a negative examination, which naturally left the 
diagnosis uncertain. Diagnoses of malaria too help to lessen the yellow fever repu- 
tation of the city. 
In some of the rubber-cutting districts in the swampy riverside forest there is 
much malarial fever. Arrangements were to have been made for us to visit some 
* Thus one has seen quinine given to perfectly afebrile cases. 
