C. M. Wen YON 
303 
of the flagellates found in Stegomyia being a cultural form of the 
sore parasite as in the case of the bed bug. 
Attempts were made to infect mosquitoes by allowing them to feed 
on the artificial culture, but with no definite result. The flagellates so 
taken up, quickly disappeared from the gut, even though the mosquitoes 
were allowed to feed on a human being afterwards. 
The experiments with the flies just recorded were conducted mostly 
on a boy of about four years of age, who had a sore of the non-ulcerating 
type on the cheek. Some were made with other patients, but the boy 
was the only one who was willing to be employed in this way regularly. 
One had to be very careful not to frighten the patient or his friends, 
who were always very suspicious of what was being done. The sore 
was a non-ulcerating one, and in order to allow house-flies to feed from 
it, it was necessary to remove some of the thin skin over it. This 
exposed the red granulations from which it was easy to obtain large 
numbers of parasites. House-flies feeding on these granulations took 
up numbers of the large infected mononuclears and also many free 
parasites. A scab formed from day to day over these granulations, and 
this was removed whenever it was necessary to feed house-flies or to 
obtain juice from the sore. 
With mosquitoes and Stomoxys it was not necessary to have the 
.scab removed, as these insects fed readily through the intact skin at 
the side of the scab. Bed bugs generally would not feed, unless the 
granulations were exposed, and this introduced a difficulty, for im¬ 
mediately the bug became in the least involved in the exudate, it 
refused to feed, and often died, especially in the case of the young bugs 
hatched in the laboratory. 
The mosquitoes were kept in glass jars as recommended by 
Christophers and Stephens in their Practical Study of Malaria. These 
jars were kept either in the laboratory or in the Sirdarb where the 
temperature was lower. In order to have a still lower temperature, 
mosquitoes were also kept in porous earthenware pots about six inches 
high and about five inches across. These were covered with mosquito 
netting and placed in a plate of water. The water from the plate soaked 
up the sides and by evaporation produced a temperature of about 70° 
to 75° F. These pots are of the same material as that from which the 
large earthenware filters or hubs are made, and it is on the moist cool 
surface of these hubs that the mosquitoes about the house repair during 
the hot part of the day. The small earthenware pots covered with 
mosquito netting reproduced the natural conditions very exactly. In 
Parasitology iv 20 
