Seasonal Reproduction in the African Olive Grass Snake, Psammophis phillipsi (Serpentes: Colubridae)

Forty-nine adult male, 30 adult female, and 46 unsexed juvenile olive grass snakes (Psam- mophis phillipsl) from Africa north of the equator were measured and dissected. Male snout-vent lengths were larger than those of females, and no dimorphism in tail length was found. Vitellogenesis commenced by the end of the rainy season, oviposition occurred by mid-dry season, and hatching occurred at the onset of the rainy season. Mean clutch size is 10.7 + 1.4 (n = 9, 6-19). No correlation between maternal snout- vent length and clutch size was detected. Testicular recrudescence began at the end of the rainy season, with regression beginning at the end of the dry season and continuing through the rainy season. Most hatchlings mature in the first year.