Dr. Zweifel 1953 Microhyla Peña Blanca Public Camp, Santa Cruz Co., Ariz. July 21, 1953 Following instructions provided by Dr. W. Frank Blair, who collected them there last night, we went to a muddy temporary pool by the roadside. A single Microhyla was calling. It is a most difficult call to locate with precision. Bill Kramer and I sat on opposite sides of the pool (about 12' apart), each insisting the frog was on the other person's shore. Eventually it was found calling from a floating position in the middle of the pond between us. The call is a high-pitched buzz. According to Dr. Blair, the call is different from that of either M. carolinensis or M. olivacea. He succeeded in transcribing it on his tape recorder.