R. Zweifel 1953 Journal 9 mi. N Mazatlan, 100', Sinaloa, Mexico July 13 of B. cognatus, being smoother, and is not a whistling triel like that of B. punctatus. The biggest surprise was the discovery of a Drymona spatulate sitting on [illegible] snag protruding a few inches out over the pond, and giving its monotonous croak. Another was seen on the branches of a dead tree fallen into the water. At least two other species gave an occasional call, but these were not found. All this was taking place in sunlight bright and warm enough that the Cromidophorus were active. The pond and stream flowing into it were very turbid with reddish-brown silt. Xindotaurus was taken in the pond. We had intended to return to the pond in the evening, but the late return of the third member of our party from a hike to the beach canceled that plan. Instead, we spent an hour driving on the highway. The only snake found was a DOR Hypsiglena torquata. Anurans were very abundant. We found many Pteromylax fodexis, and also Smilisca baudini, Bufo mazatlanensis, and Bufo horribilis, and Leaphisopus coucli. In addition, earlier in the evening I had found a Hypopachus on the dirt road by our camp. Minimum temp 71°F, Maximum 93° F. Also collected today were Cromidophorus sarki, Sceloporus clarkii, Andlos, and Oxybelis aeneus.