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PACIFIC SCIENCE, Vol. IV, October, 1950 
a few days after it was dropped and the 
epiphragm broken. Another snail lived for 
5 Vi months in an outdoor cage without food. 
During unfavorable conditions snails were 
observed to secrete a brown calcareous epi- 
phragm over the aperture. In the field it 
was noted that certain snails with epiphragms 
remained in an inactive condition regardless 
of adequate moisture. In this case it was 
thought that inactivity was not correlated 
with wet and dry conditions at the time, 
but with the physiological condition of the 
snails or status of development of the female 
structures. 
NATURAL ENEMIES 
A few natural enemies of Achatina fulica 
are reported in the literature. Green (1911: 
43) lists enemies in Ceylon as the common 
pond tortoise, Nicoria trijuga var. ther malts ; 
an ant (Pkeidologeton affinis ), which attacks 
the eggs; insectivorous birds; and carnivorous 
beetles. 
Bequaert (1925:201; also in Pilsbry, 
1919:61-63) records minute, ectoparasitic 
mites on a living Achatina in the Belgian 
Congo and mentions the wingless flies of the 
genus W andolleckia (family Phoridae), which 
live in the adult stage upon the slime of 
Achatina. 
Jarrett ( 1931 :263-264) records the In- 
dian firefly, Lamptophorus tenehrosus Wit, 
as an important parasite of young Achatina 
fulica. 
In the Marianas no effective natural ene- 
mies of the giant snail were observed, and 
the toad Bufo mar'mus , supposedly introduced 
to feed upon snails, took no appreciable toll 
On March 13, 1948, a few snails on Saipan 
and Tinian were found in a moribund condi- 
tion although the cause of sickness was not 
determined. The bodies of the snails became 
Fig. 8. Aggregation of Achatina on Tinian airstrip, March 13, 1948. Several hundred, snails were 
found in an area of approximately 54 square inches. 
