Urucúm proved to be a garden spot of clear, cold springs, shady groves, and plantations of tropical fruits and vegetables. In the centre of all stood comfortable cottages with large, well-ventilated rooms and delightful shower-baths. Fields and forested hillsides, marshes, and lagoons were easy of access; in them dwelt an abundant and varied fauna. A grove of magnificent mango-trees grew near the house that had been assigned for our use; hundreds of bats came to the trees each morning just as dawn was breaking, to seek their diurnal sleeping-quarters among the dense foliage. They arrived in unbroken streams and spent a great deal of time whirring through the branches, squeaking and making queer little noises that sounded as if they were grating their teeth. Then they finally settled in clusters of from six to a dozen individuals in some particularly thick clump of leaves and, suspended by the claws of their hind feet, began their daytime slumbers. On windy or rainy days they lost little time in becoming settled, and did not seek the swaying branches, but clung to the tree-trunks or on the under-side of the thick limbs. This species of bat (_Vampyrops lineatus_) has a leaf-shaped appendage on top of the nose which may be of some use to the animal, but is probably of little consequence. This “leaf,” the nose and face, including the tips of the ears, were tinged with delicate green. As the bats hung head downward, the green-tinted extremity naturally pointed toward the earth; but if the color was intended as a protection it was of little or no avail, as it could not be seen unless the animal was examined at close range. Other individuals of the same species were collected in a dark cave in the near-by mountains. They, however, showed only a very faint or no trace at all of the green coloring on the face. I am convinced that this color is not a vegetable stain, but that the pigment exists in the skin; it fades soon after death.