R.K. Selander, 1952 14 July 28 Rio Mztzlitan, 4000 ft., 20 mi. N Atotonilco, Hidalgo, Mexico. today. Collected several lizards, including one on the trunk of a large black walnut tree - took one of these yesterday on the trunk of a walnut tree. lizards are abundant in the drier spots all along the stream - most active in the morning before 10:00. Skinned in afternoon; made a skeleton of one of the wrens; also preserved a wren in formalin. Both flying over stream at 8:00. Weather very fine tonight - clear, moderately warm. Stomach somewhat better today - have been taking sulfadiazine - will stop treatment now - see what happens. This is a good camp spot - the only disadvantage being the numerous forms nearby: Mexican children and adults continually passing and stopping to look into our tent. The river is too muddy to drink, but there is a small stream spring near the river where reasonably clear water can be obtained. We are boiling all our water, even that used for washing. On the following page is a rough sketch of the area in which we are camped: