Journal Hamner, M.S. 1979 Vicinity Mazatlan, Sinaloa, Mexico 3 July (cont) water) and headed south on the main highway. Turned north at Villa Union and ca. 1200 arrived at Sigueros. We then drove to a point 1 km N Sigueros. We had trapped Thomomys at this locality in late July, 1977. I still was feeling rather ill so John set out 6 sets. The heat was extremely oppressive. John worked the sets most of the pm and caught a total of 3 gophers. He and I set out a total of approximately 13 sets - gophers were very hard to find. Just before sunset, John pulled-in a live male! Much needed for karyotyping. NORTH Rio Presidio SAND (few trees) DIRT ROAD over-grazed area w/some trees SAND WASH OLD CORN FIELD FIELD gophers were along the edges of these fields - burrows were almost always in the surrounding natural habitat. Sigueros