Feathers. 1934. Colorado R., 1/2 mi. N Nev. - Calif. 39. monument, Clark Co., Nev. Feb. 3, 1934. My traps across the slough were visited after the departure of Drs. Brown and Hall. None of the traps were disturbed. I set out seven more traps in the willow association, using two costs for bait. I returned to camp and put up the skin of the blue heron. That task required five hours of my time. During that period, Mr. George Snyder brought in a beaver, which he had caught at the river's edge, west of camp 3/4 of a mile. He had used a boat to set his traps. He stated that beaver are difficult to catch, when traps are set from the bank, the human scent which is left by the trapper, causing the animal to take fright, as it approach es the bank. I accompanied Snyder north along the slough one mile, to a place where muskrat traps had been set by Dr. Hall and myself. One muskrat was found in the trap set by Dr. Hall. The other two traps had not been disturbed. I set one more trap at this place, and three at other places near there. The muskrat dens were observed as genera- ally being located in the banks under the protection of a mesquite tree, or dense growth of arrowweed. The den entrances were four to six inches below the surface of the water.