Early in 1960 an unusual opportunity arose to carry on biological field<br />work in the midst of virgin rainforest in southern El Pet&eacute;n, Guatemala.<br />At that time the Ohio Oil Company of Guatemala had an air strip and camp<br />at Chinaj&aacute;, from which place the company was constructing a road<br />northward through the forest. In mid-February, 1960, J. Knox Jones, Jr.<br />and I flew into El Pet&eacute;n to collect and study mammals, reptiles, and<br />amphibians. While enjoying the comforts of the fine field camp at<br />Chinaj&aacute;, we worked in the surrounding forest and availed ourselves of<br />the opportunity to be on hand when the road crews were cutting the tall<br />trees in the forest, thereby bringing to the ground many interesting<br />specimens of the arboreal fauna. We stayed at Chinaj&aacute; until late March,<br />with the exception of a week spent at Toocog, another camp of the Ohio<br />Oil Company located 15 kilometers southeast of La Libertad and on the<br />edge of the savanna. Thus, at Toocog we were able to work both in the<br />forest and on the savanna. In the summer of 1960, John Wellman<br />accompanied me to El Pet&eacute;n for two weeks in June and July. Most of our<br />time was spent at Chinaj&aacute;, but a few days were spent at Toocog and other<br />localities in south-central El Pet&eacute;n.