THE YELLOW-FEVER MOSQUITO. 5 
long association with man is shown by many of its habits. It ap- 
proaches stealthily from behind. It retreats upon the slightest alarm. 
The ankles and, when one is sitting at a table or desk, the underside 
of the hands and wrists are favorite points of attack. It attacks 
silently, whereas other mosquitoes have a piping or humming note. 
The warning sound has doubtless been suppressed in the evolutionary 
process of its adaptation to man. It is extremely wary. It hides 
wherever it can, concealing itself in garments, working into the 
pockets and under the lapels of coats, and crawling up under the 
clothes to bite the legs. In houses it will hide in dark corners, under 
picture moldings, and behind the heads of old-fashioned bedsteads. 
Tt will enter closets and hide in the folds of garments. 
HABITS OF THE ADULT. 
FEEDING HABITS. 
The female sucks blood when it is available, and needs blood to 
develop her eggs. In captivity she has been kept alive for a long 
Fig. 3.—The yellow-fever mosquito: Adult female, side view. Much enlarged. 
(Original. ) 
time on honey or other sweet substance. She is attracted to portions 
of the body covered with perspiration. A female will bite within 18 to 
24 hours after she emerges from the pupa. Virgin females will bite, 
but fertilized females are more greedy. After a meal of blood she is 
very sluggish; she flies with difficulty, seeking a hiding place for 
digestion. Several hours are consumed in digestion, and then the 
female is anxious for another meal of blood. The species normally 
sucks blood repeatedly. In 31 days a female is recorded to have 
sucked blood 12 times. By biting a number of different individuals 
the chances of becoming herself infected with yellow fever and trans- 
mitting the disease are greatly increased. 
The yellow-fever mosquito can subsist upon the blood of any warm- 
blocded animal, but shows a decided preference for man. It prefers 
the white race to dark races, and among the whites attacks by pref- 
erence young, vigorous persons of fine skin and good color rather 
547 
