R. Zweifel 1953 Journal July 5 get onto the road to Ojito and El Vergel from the end of the pavement at San Francisco del Oro, it is necessary to keep to the right, putting the largest pile of gray sand to your left, passing by the golf course (with paved blakctop greene) and out through the middle of the trash dump. 90.0 mi. Durango. We spent the night the night with the Bryans who had foolishly asked us back. July 6 We left Parral at about 10:00 AM, driving south for Durango. At the Rio Florido we stopped for lunch and spent some time collecting. Both Thamnophis eques megalops and Thamnophis melanogaster were found here. The river is 10-15' wide and one foot deep. There are walnuts and cottonwoods shading parts of the stream. Elevation 6100'. The surrounding countryside shows rolling, nearly barren hills supporting a few scrubby oaks. Our next stop was at the Rio Nazas. Strikingly colored Cnemidophorus sakti were common along the river. Sceloporus undulatus was taken from tree trunks and Holbrookia tevenna from sandy areas near the river. This is an mesquite - oortillo desert. A large gopher snake was purchased from two Mexicans