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JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 16 
to three-fourths inch in greatest diameter. The body is light cream to 
dark gray and in the adult has an extension of one and a half to two 
inches. As there is no operculum the aperture is sealed with a temporary 
epiphragm during drought or other unfavorable conditions. 
This snail is hermaphroditic and mutual fertilization is necessary for 
reproduction. Mating begins in the fall when the first rains come and 
oviposition follows from a few days to several weeks later. At La Jolla 
mating under natural conditions was first observed November 9 after 
a good rain had fallen during the night. The first snails were found 
ovipositing on November 30 after several days of wet weather. When 
ready to lay eggs the snail digs a hole in the ground about one and a 
half inches deep and enlarges the lower end to form a cavity for the egg 
mass. As the genital aperture is at the anterior end the snail does not 
withdraw its body from the hole until the entire process of digging and 
egg laying is finished. The soil is dug loose by the lips and jaw and 
worked out along the lower side of the foot in a flat ribbon onto a little 
conical pile to one side of the shell. The eggs are deposited singly but 
adhere to each other as they emerge, forming a mass that looks much 
like a white blackberry. They are spherical, about two millimeters in 
diameter and milky white. When through laying eggs the snail with¬ 
draws from the hole and carefully closes it at the top with mucus and 
bits of soil, and then crawls away. The whole process requires several 
hours. According to T. de Stefani (2) each adult oviposits but once in a 
season; however, as the generations overlap, egg laying continues from 
the beginning of wet weather in the fall to the dry season in the spring. 
He gives the number of eggs deposited by a single individual as from 
fifty to seventy. At La Jolla in December 1922 the number of eggs in 
twelve egg-masses ranged from fifty-two to two hundred and twenty- 
six. The average was one hundred twenty. The number of eggs 
would no doubt vary according to the age and size of the snail and 
perhaps also with weather conditions. 
The time of hatching, of course, depends on favorable temperature 
and moisture. In Europe T. de Stefani says it is twelve to sixteen days. 
At La Jolla it was about three weeks. Eggs laid on the last of November 
hatched about December 20. The newly hatched snails have a very 
thin shell of one and a half whorls. The adult snail has five whorls and a 
fairly hard shell. Shortly after hatching the young begin to feed on the 
tender plant growth in the vicinity of the nest. Of the snails hatched 
on December 20 the largest one was about three-eighths of an inch across 
at the end of fourteen weeks. Besides feeding on nearly all kinds of 
