through which extend ridges of Pennsylvanian limestone. These are on both sides of Sawmill canyon, but the eastern side is marked in Schraders Pm. (Devonian). There is no Devonian here but I did not see it; all the forms down are clearly Pennsylvanian. Left a few forms and turned west to Strugman. For more detail see F.C. Schrader in Bull. 582 (1910) J.S. S.D., "Mineral Deposits of the Santa Rita and Patagonia Mts." After seeing the basal Devonian in the Whetstone Out it is now clear that I did see very similar Dev. in Sawmill Canyon. Above the Devonian must be some Mississippian since I did not get Pennsylvanian until well up on the ridge east of the canyon bottom. The Penn. has helms (in east side) a post-herd formal (large B. crassus) and listra of a deeply eroded Productus outcrop of late Penn. Saw no Strigman Camunatus