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~ LFL COLLECTION POLICIES AND PROCEDURES MANUAL 6 isopropanol. Specimens cleared and stained for skeletal study are maintained in 70% ethanol or 100% glycerol. Specimens received in special preservatives (e.g., glutaraldehyde, color preservatives) are maintained in those preservatives whenever practical. For cataloged collections, current preservative is recorded in the collection catalog and on lot labels. Unless the depositing agency reports otherwise, it is assumed that 95-100% alcohol-preserved specimens were fixed in that preservative and that formalin and lower-concentration alcohol- preserved specimens were initially fixed in 5-10% formalin. Significant deviation from these protocols, if known, documented as remarks in the collection catalog. Backlog collections are usually maintained in their initial preservative but if notably changed, such is documented on supplemental container labels and in associated collection files. Collection containers are filled as completely as practical with preservative to avoid drying of specimens and aid inspections for poorly sealed containers. All collections are checked annually for loss of preservative. Dried specimens, if kept, are usually maintained in that condition and so noted in associated collections files or the catalog. Specimens or parts thereof that are not maintained in fluid preservatives are maintained according to their preparation. Voucher, Study, and Reference Collections-Voucher collections are preserved specimens usually collected at a specific location and time. As such, they represent a specific historical occurrence and irreplaceable sample of natural history. They are often taken as part of organized field investigations. When collections are readily identified and processed in the field, voucher collections may consist of only one or more specimens that vouch for each taxa and sometimes each developmental interval or age-group reported during that investigation. Unusual or questionable specimens are also typically preserved. However, when working with unfamiliar taxa or specimens that are difficult to identify and process alive in the field (e.g., early life stages of fish), collections are necessarily preserved for each site and time sampled. Sometimes voucher collections are an aggregate of specimens taken at different locations and times during an investigation; as such they no longer vouch for taxa (and life stages) taken during specific collecting events, but they still represent taxa reported to have been taken over the associated range of collection sites and dates. LFL voucher collections are stored on shelving according to container size (vials or a mix of larger containers) and ordered sequentially within those groupings by catalog number. When possible, all lots from the same voucher collection and all collections from the same investigation are cataloged and stored together (except for storage separation according to container size). Study collections consist of preserved specimens that do not represent a historical, natural occurrences or for which such associated collection information has been lost. Such specimens may have been artificially reared, preserved during or at the conclusion of laboratory or field experiments, or selectively and permanently removed from voucher collections for morphological examination, descriptive study, or other educational or research purposes. If possible when study specimens are removed from voucher collections, links to source lots are maintained in the collection catalog. Reference collections are usually specimens selected from voucher and (or) study collections that are conveniently organized to aid taxonomic identification by comparison with collected material. Again, if possible, links with source lots are maintained in the collection catalog. Study and reference collections are organized on shelving phylogenetically (by species) then by catalog number (except for separation according to container size).