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Macroscopic and histological observation of the skin and the thumb pads on adult male toads weighted 27-30 gr were studied under defined conditions (Room temperature 20-25C and photoperiod of 12L: 12D). Groups of animals received intraperitoneally injection of whole female pituitary gland and different doses (25, 50, 100, 200 IU) of HCG and (0.5,2.0,5, 10jig/g B.W.) of testosterone. Studies on experimental animals showed increase in thickness, pigmentation, number of dermal glands and epidermal papillae in thumb pads and skin in all groups. Injection of different doses of testosterone in castrated males showed the same results. The effect of sexual hormones on the thumb pads and skin appear to be related to the androgen receptors in these organs which become active during reproductive period and sexual behaveiour.