The Field Museum is one of the world's largest repositories of bulk arthropod samples, collected by museum staff and associates and by collaborators from numerous other institutions. The majority of these are samples of soil and litter faunas (mostly from forests) around the world, extracted by use of Berlese funnels or other means including deep-soil washing, and mostly stored in 70% ethanol (a few in 95% ethanol). Most samples have ecological data on habitat and/or collecting substrate. At around 15,000 samples, this is probably the largest such collection in existence. Most samples have had some taxa removed (especially beetles, mites, spiders, and millipedes), but still contain vast numbers of other arthropods. In addition to the soil and litter samples, there are also samples from some 4,000 trap collections (flight intercept, pitfall, dung- and carrion-baited pitfall, and blacklight) and small-scale pyrethrin-fogging of substrates such as logs. Much of the sorting done on-site has been supported by collection improvement or research grants to curators in the Division of Insects. We encourage researchers to visit and seek material of their study taxa from these samples.

This organized collection was begun by former curator Henry S. Dybas (1915-1981, curator 1947-1980), a dedicated "niche collector," who began giving each sample of his a unique number of the form FM(HD)#-year-000, where "year" is the year of collection and 000 is a sequential sample number within that year. The (HD) suffix - his initials - served to distinguish these numbers from Field Museum catalog numbers in other divisions or departments; the parentheses were later eliminated for simplicity. When the museum's name was Chicago Natural History Museum (1953-part of 1966), the prefix CNHM(HD) was used, so specimens sorted and prepared then will be so labeled. All those samples are nevertheless entered here as "FMHD" numbers to simplify use of the data. All available collecting data for each sample are presented.

Searches are automatically performed as whole-word wildcard searches; data for a sample with a known FMHD number can be found by entering the year-000 part of the number in the Sample Number field. There are some inconsistencies in the data, e.g., "National Park" may be abbreviated N.P., Nat. Pk., Natl. Pk., or (in Spanish-speaking countries) P.N. and distances from a named place are written in different forms, so searching for just the key words in names (e.g., Olympic, Puyehue, Border Ranges) or localities is recommended.

Partial words may be entered using an asterisk (*) for a wildcard (e.g., ). Searches will take more time with wildcards. If you choose to enter more than one term in a field, only records with both terms will be returned.

Users should note that the prefix "BS-" numbers used for collecting sites are database-generated site numbers; they have no historical significance and are not present on the specimen labels.

As the vast majority of records will not have images, choosing the "List items only with images" will have little if any effect on the query result.