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PACIFIC SCIENCE, Vol. IV, October, 1950 
Fig. 2. Achatina fulica and eggs, Saipan, October 29, 1947. 
and it was noted that individuals crawling 
about in trees during the day occasionally 
extruded the genital organs. 
In mating one snail usually climbs above 
another, the organs are interchanged, and 
both snails fall to one side, remaining to- 
gether for a period varying from less than 
1 hour to 24 hours or more. The manner of 
mating is shown in Figure 3. Snails collected 
during coition were held in the laboratory in 
gallon cans which had been filled with 4 
inches of moist soil. After mating, eggs were 
deposited in from 8 to 20 days, with an aver- 
age interval of 10 to 12 days. On Saipan a 
preferred site for egg deposition was under 
loose soil at the bases of breadfruit trees as 
shown in Figure 4. Eggs were also laid under 
rocks, boards, or other objects, or in the soil 
wherever there was a cover of vines, shrubs, 
or trees. Eggs were often merely scattered 
about on the surface of the soil or barely cov- 
ered, and rains often exposed many of these. 
Usually a snail made a depression about 2 
inches wide by 1.5 inches deep in loose soil 
in the ground, deposited its eggs, and covered 
them with soil. 
Egg masses were found in the field from 
October 16, 1947, to November 11, 1948. 
The presence of young snails on October 1 6, 
1947, indicated that eggs had been laid prior 
to this time. The number of eggs laid in the 
field varied from 93 to 184, with an average 
of 139 eggs. In the laboratory, egg deposi- 
tion was observed from October 30, 1947, 
to November 19, 1947; the eggs were laid 
in gallon cans filled with 4 inches of soil. 
The number of eggs laid by individual snails 
in the laboratory varied from 62 to 243, with 
an average of 129 eggs. 
In captivity most of the snails laid their 
eggs during one night, but occasionally an 
