The Forebrain Atlas of the Short-tailed Fruit Bat, Carollia perpicillata, is unique among brain atlases. Not only is this the first quality atlas treatment of a bat species, but the atlas is also unique in its use of NeuN staining. Carollia perpicillata, a tropical species, is the only bat that has essentially been domesticated and can be maintained and propagated in a research environment utilizing simple, inexpensive husbandry procedures. The NeuN preparations used in this atlas selectively stain neurons in a sharp black coloration that fills not only the cell body but extends a short distance along the proximal dendrites. Thus, as distinct from the traditional nissl stains, which generate a shade of blue largely restricted to the cell body, the NeuN generates a quasi Golgi-like image of the neurons. This provides a more intimate view of the neurons than can be obtained from nissl staining. In addition, the background is essentially white, facilitating high-contrast photography and allowing for gray-tone illustration without any loss of information. The NeuN procedure does not stain axons, and since it does not stain glial cells or their nuclei, the noise ordinarily generated in nissl stains by the presence of glial cells among the neurons and in the white matter is entirely eliminated. The Forebrain Atlas of the Short-tailed Fruit Bat also includes nissl stained sections for two reasons: One, since some readers may be unfamiliar with the NeuN images, it is useful to include familiar images for comparison. More importantly, it is known that NeuN is not expressed in certain neurons, such as Purkinje cells, olfactory bulb mitral cells, and the cells of the paraventricular and supraoptic nuclei. The nissl stained sections are thus included to provide complementary views of such structures. The atlas will be useful for students and investigators doing neuroscience research on bat and other mammalian species,as well as students of comparative biology, zoology, brain evolution, and the history of neuroanatomical analysis.