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pupe. A single male will fertilize a number of females, and Low 
has observed in the West Indies that they copulate by night as 
well as during the day. 
The adults under certain conditions can live for a considerable 
time. They have been known to live on board ship for forty-seven 
days, and BANCROFT in Queensland has kept females in confine- 
ment for two months. This longevity of the adults is very import- 
ant, and explains how several outbreaks of yellow fever have 
occurred where the species is not indigenous. 
REED has pointed out that this insect dies within five or six days 
when deprived of water; it is not likely therefore that it can be 
imported in trunks or crates of bananas, etc. I think however that 
this statement wants verifying, as I remember having kept one 
alive for ten days in a glass top pill box. 
The general facts of the life-history have been traced out by 
GOELDI (1905), GRABHAM (1905) and others. 
The ova are laid separately, not in rafts as in the genus Culex. 
According to GRABHAM, they may be laid in chains, about a 
quarter of an inch between each egg. 
BANCROFT (1908) has also noticed the same in Queensland, 
stating that they are laid « singly on water in chains with an inter- 
val between each egg of a quarter of an inch or more ». Those 
figured by GOELDI (1905) do not show this chain-like appear- 
ance. 
In colour the ova are black, elongated oval in form and com- 
pletely covered with a reticulated membrane; with air in some of 
the reticulated cells. _ 
The incubation period varies, but is somewhere between 6 and 
20 hours. 
NEWSTEAD (1910) found it to vary between 6 and 12 hours. The 
larval stage lasted 9 days. The pupal stage 3 days. The complete 
life-cycle thus possibly taking only 12-13 days. DURHAM (1901) 
found in Para that the first pupa occurred on the 8th day, and 
hatched into a male on the roth day, and others on the 12th day. 
A technical description in English of the larva and pupa may be 
found in the « Bulletin of Entomological Research (1) ». 
(1) W. WESCHÉ, «On the larval and pupal stages of West African Culicidæ », 
vol. 15, pt. 1, p.25, 1910, 
