Development of Egg Masses in Fresh Water Pulmonate Snail Indoplanorbis exustus

Abstract

Egg capsules were generally laid at night or early in the morning by I. exustus. The freshly laid eggs varied from 4.0 to 5.0mm in their diameter. Each egg mass of I. exustus was observed as flattened and like a coiled whorl. The proper egg capsules of I. exustus were flattened, oval and rectangular and had a diameter from 0.5 to 0.7mm. The egg capsules lie side by side in 2-3 rows. The shape of egg capsule was more or less rectangular, the average length being 0.7mm and width 0.5mm. The number of capsules varied in each egg mass. In I. exustus, they were generally 7-60. Normally each capsule contained only one egg.