Variation in external and internal characters of the endemic Tanzanian species Geodipsas vauerocegae and G. procterae have been examined. On the basis of the small sample sizes, no significant geographical differences can be demonstrated. Three recently collected specimens from the Udzungwa Mountains, however, seem to have slightly lower numbers of ventrals than those from the Uluguru Mountains. All available knowledge on the natural history of the species has been summarized