Abstract
Mating, oviposition, post-oviposition period, development, and generation period of the two land snail species Monacha cartusiana (Muller) and Eobania vermiculata (Muller) were studied in the laboratory in Egypt during the two seasons of 2003/4 and 2004/5. Data revealed that mating is essential for both snail species to lay eggs, thus it occurs when snails reached their sexual maturity (from adulthood till mating) during a period averaged 190.3 and 228.6 days for M. cartusiana and 231.6 and 568.3 days for E. vermiculata after adulthood in the two different seasons respectively. Pre-oviposition period (from mating till laying first egg) lasted an average of 2.7 and 8.2 days for M cartusiana and 3.5 and 9.2 days for E. vermiculata during the two seasons respectively.
Oviposition period (from first laying egg till last one) averaged 22.5 and 64.1 days during which the snail of M cartusiana deposited an average of 63.0 and 177.5 eggs during the two seasons respectively. On the other hand this period averaged 15.2 and 24.9 days for E. vermiculata during which the snail individual deposited and total average of 89.6 and 162.0 eggs during 2003/4 and 2004/5 respectively. While, post-oviposition period (from last egg till death) lasted 142.4 and 71.9 days for first snail species and 372.5 and 660.1 days for the second one during the same seasons respectively. The generation period (from egg to egg) extended an average of 369.8 and 402.6 and 481.7 and 868.7 days for both species during the same seasons respectively.