The effect of testosterone on the histological pattern of the gonads of the land snail Theba pisana was studied. It was found that testosterone accelerated spermatogenesis, as indicated by the large increase in the number of spermatozoa and the decrease in the number of primary spermatocytes. The diameter of the acini in treated snails was greater than in the normal controls. Conversely, testosterone led to reduction of the number of mature ova.

Department of Zoology Faculty of Science Menoufia University Shebin El Koom Egypt