Library of Congress Subject Subdivisions

[   Introduction  |    Types of Subject Subdivisions  |    Special Rules for Geographic Subdivisions  |    Sources for Free-Floating Headings  | 
  Library of Congress Subject Headings  |    Table of Contents (Subject Analysis)  |   Table of Contents (Top)]

Introduction

The Library of Congress Subject Headings include, besides all the main headings, various subdivisions used following main headings to add specificity to the subject entry.

Subdivisions may be authorized specifically for one main heading and never used anywhere else.

600 00 |a Napoleon |b I, |c Emperor of the French, |d 1769-1821 |x Captivity, 1815-1821.

Others are authorised for use with main headings in only one or a few general subject areas.

650 0 |a Swedish language |x Grammar.
630 00 |a Bible |x Reader-response criticism.

Many subdivisions are authorized for use under a wide variety of main headings.

610 10 |a Canada. |b Parliament. |b Senate |v Biography.
650 0 |a Women in politics |z Canada |v Biography.
651 0 |a Kingston (Ont.) |v Biography.

LC has been working for some time toward standardizing the subdivisions more and more. See Sources for Free-Floating Headings for information about lists of "free-floating" subdivisions for use in particular cases.

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Types of Subject Subdivisions

Subject subdivisions fall into four groups which are given different subfield codes:

The original RECON project at Queen's coded all subject subdivisions as |x. Many of these are still in the database. In addition, the |v Form subdivision is a relatively new innovation, so records imported even from the best sources before the late 1990s will have |x where we would now use |v. These older codings may be corrected if you are already working on a record, but you should not spend time correcting large numbers of them. They do not (so far) have any effect on the OPAC.

Period subdivisions may be used alone under some main headings in literature and music, but otherwise they should be used only after |x subdivisions such as History where they are specifically authorized. Under places, |x History and |x Politics and government may have authorized period subdivisions appropriate only to the history of that particular place.

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Special Rules for Geographic Subdivisions

Note that two, but not more, geographic subdivisions may be used when the place to be designated is within a larger place. The general rule is that the first |z is used for the name of the country, the second for the city or other lower-level place. In most cases, this can be done by moving the qualifier in the established heading into the first |z and spelling out the abbreviation if any. There are a number of special cases; some that come up often are:

• If the country is Canada, Great Britain, or the United States, replace the name of the country in the first |z with the name of one of its major parts.

  Country	Major part	Established heading	Subdivision
  Canada	Province	Halifax (N.S.)	Nova Scotia |z Halifax
  Great Britain	Constituent country	York (England)	|z England |z York
  United States	State	Boston (Mass.)	|z Massachusetts |z Boston

  These three countries are also never used as qualifiers in authorized place name headings. Of course they can be used in 651 fields and |z subfields when the work is about the country as a whole rather than one of its parts.

• Three other countries, Australia, Malaysia, and Serbia and Montenegro, are used in geographic subdivision but not as qualifiers. This sometimes creates a situation where you would like to have three |z subfields because there are really three levels involved. Instead, leave the middle-level qualifier in the second |z subfield (e.g. |z Australia |z Sydney (N.S.W.)).


• If the place is a river or other feature located in two countries, provinces, etc., the authorized heading may include a double qualifier (e.g. Ottawa River (Quéebec and Ont.)). Leave the double qualifier in the |z subfield, instead of inverting with two |z subfields.


• If the city is Jerusalem or Washington (D.C.), omit the name of the higher-level entity.

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Sources for Free-Floating Headings

The Library of Congress publishes an annual volume with the title Free-Floating Subdivisions : an Alphabetical Index (uncatalogued in CTS). Recent editions are on the desks of various staff members in Cataloguing. This work lists all the authorized "free-floating" non-geographic subject subdivisions, indicating for each:

• whether it can be followed by a geographic subdivision
• which code (v, x, y, or z) should be used
• what categories of main headings it may be used under
• where to find more information in "SCM:SH"

SCM:SH, or Subject Cataloging Manual : Subject Headings, is found in four large red binders in the Cataloguing area, or online on Cataloger's Desktop. It is divided into sections numbered H1 through H2400 (though not all the numbers have been used), which lay out LC's policies for assigning subject headings to various types of material. Among other things, it contains lists of free-floating subdivisions authorized for use in particular situations.

Note especially section H1095, which lists subdivisions that may be used under any main heading, frequently with notes indicating the most appropriate use. Others that are most useful include H1100 (Classes of persons), H1105 (Corporate bodies), H1110 (Names of persons), H1140 (Places). There are also lists for Animals, Legal topics, Religions, Wars, etc., and sections on Art, Dictionaries, Manuscripts, and many other things. The information above about Geographic subdivisions comes from the same manual.

The LC subject authorities imported into Voyager at Queen's include authority records for subject subdivisions. Search in the Staff Subject Subdivision index to find the authorities, often with helpful notes, and also all the cases where that subdivision has been used in our database. (It is not advisable to search for a common subdivision like —History, since there are so many examples the search is very slow.)

If multiple subdivisions are being used in a single subject field, determine whether the |x subdivision is one which may be subdivided geographically. If it may, the normal order of subfields is |x |z |y |v. If not, the order should be |z |x |y |v. This is important to keep the index consistent.

650 0 |a Land reform |x Government policy |z Brazil |z Paranéa (State) |v Bibliography [—Government policy may be subdivided geographically]
650 0 |a Peasantry |z Ecuador |x Political activity |x History |y 20th century |v Sources [—Political activity may not be subdivided geographically]

Other variations may occur. For more details, see SCM:SH, section H1075.

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Created June 18, 2004 by D. Rutherford