11 the Farlow Herbarium unless I have indicated otherwise. Slides placed in this collection have been verified as being Bailey's based on their having 1) serial numbers between 567 and 2,185, 2) descriptions consistent with those of similarly numbered entries in the Catalogue of the Bailey Microscopical Collection, 3) notations in Bailey's handwriting scratched on the slide, 4) notations in Bailey's handwriting on papers associated directly with them, and 5) a system of standard reference lines, orientation arrows or numbers characteristic of Bailey's "Universal Indicator" method of locating individual specimens (Bailey, 1855). Slides falling harmoniously into a series ordered on the basis of the preceding criteria were also included. I have marked each slide appropriate to this collection by placing on it a round, 0.8 cm diameter, white label bearing the slide serial number. The slides have been placed in numerical order in 18 wooden slide boxes, which were remilled to accomodate the varying dimensions of the slides; grossly oversized slides have been housed separately in Box #19. A paleograph collection has been established incorporating all papers bearing notes, numbers or any writing whatsoever that were found associated with the slides. The paleographs have been referenced under the serial number of the slide with which they were found associated in 1976 unless this association was clearly in error. The serial list in this work describing the slide collection is arranged in groups of slides, partially of Bailey's design as reflected in the Catalogue and partially my own, and it includes all slide serial numbers between 567 and 2,185 eventhough some groups do not contain diatom material. This list records all information available on the slide and in the Catalogue and paleographs, except taxa determinations which have been separately indexed. The current existence at the Farlow