Fluorescent neuroanatomic techniques, such as immunofluorescence and retrograde and anterograde tracing studies, derive great utility from their specificity. However, the specificity can be a drawback as well, in that it may be difficult to assess labeled neurons or neural processes in their cytoarchitectonic context. We report the characteristics of a newly synthesized fluorescent counterstain, Fluoro Nissl Green (3,8-diamino-10H-quindoline) with spectral characteristics similar to fluorescein. This Nissl-like counterstain can be used as a green neuronal counterstain for red-emitting markers such as rhodamine and Di-I.