FIG. 4. Glacially striated diabase, made in early Permian 

 time. Vaal River north of Kimberley, South Africa. 

 Photograph by W. M. Davis. 



FIG. 5. Lower Cambrian quartzite, striated in early 

 Permian time. Inman valley, South Australia. 

 Photograph by T. W. E. David. 



