Most books and periodicals in the UM-St. Louis Libraries are arranged on the shelves by the Library of Congress (LC) Classification system. This system, like the familiar Dewey Decimal Classification, allows the materials to be grouped by topic. This grouping is achieved by assigning a "call number" to each book.

LC call numbers consist of a combination of letters and numbers and are arranged on the shelves in alphabetical and numerical sequence. They have three or more lines; the first consists of one or more letters representing the broad subject material of the book. The second line is a whole number (1-9999) representing a narrower topic within the broad subject. The third and subsequent lines consist of a letter/decimal combination or a decimal alone. These may represent a further subdivision of the topic or an author designation.

Call numbers are shelved first in alphabetical order by the letters of the first line, then numerically by the whole numbers of the second line. The third and subsequent lines are arranged alphabetically and decimally.

When checking the LIBRARY CATALOG to find a call number, please make a note of the "Location". This tells you if the item is on the UM-St. Louis campus or another campus within the MERLIN and MOBIUS catalogs. MERLIN includes the four University of Missouri campuses and St. Louis University. The MOBIUS catalog includes most universities and colleges in Missouri.

UM-St. Louis Libraries holdings begin with UMS. The Thomas Jefferson Library materials are marked TJ, the Ward E. Barnes Library materials are marked BARNES, and the Mercantile Library items are marked MERC. "Location" designations will also specify if the material is in a special area within the Libraries. For example: if you were to search for the Standard & Poor's Register of Corporations, Directors and Executives, the LIBRARY CATALOG would present a screen with title and author information and a location box similar to this:

This list gives a breakdown for some of the general subject areas of the LC Classification System, divided by the level. Level designations are for the general book collection only. Although LC numbers are also assigned to periodicals, reference books, and other special materials, they generally are not shelved on Levels 4 and 5. Please consult Library Catalog for location codes.

LEVEL 1 now houses most circulating items with call numbers beginning with A - F.
LEVEL 4 now houses most circulating items with call numbers beginning with G - Z.
LEVEL 5 now houses most journals including current issues, bound volumes, and microforms; some journals are housed in COM 2, on level 2. The catalog record will contain location information.

A - General
            AE - encyclopedias
            AI - indexes

B - Philosophy, Religion
            B to BJ (except BF) - philosophy
            BF - psychology
            BL to BX - religion

C - History (general)

D - History (except the Americas)
            DA - Great Britain
            DC - France
            DD - Germany
            DK - Soviet Union (Russia)
            DP - Spain
            DS - Asia
            DT - Africa

E - The Americas (general) and United States (general)

F - United States (local) and other North & South American countries

G - Geography, Anthropology, Recreation
            GN - anthropology
            GR - folklore, manners and customs
            GV - sports and recreation

H - Social Sciences
            HA - statistics
            HB to HF - economics
            HG to HJ - finance
            HM - sociology
            HV - social pathology, social and public welfare, criminology
            HX - socialism, communism, anarchism

J - Political Science
            JK - United States
            JX -international law

K - Law
            KF - United States
            KFM - Missouri

L - Education
            (materials housed at Ward E. Barnes Library
            on the South Campus)

M - Music
            ML - literature of music
            MT - musical instruction and study

N - Fine Arts
            NA - architecture
            NB - sculpture
            ND - painting

P - Language and Literature
            PA - classical language and literature
            PC - Romance language
            PD - Germanic language
            PG - Slavic language
            PJ - Oriental language and literature
            PN - literature
            PQ - Romance literature
            PR - English literature
            PS - American literature
            PT - Germanic literature

Q - Science
            QA - mathematics
            QB - astronomy
            QC - physics
            QD - chemistry
            QE - geology
            QH - natural history, general biology
            QK - botany
            QL - zoology
            QP - physiology
            QR - microbiology

R - Medicine (most items are housed at the Ward E. Barnes
            Library on the South Campus)
            RE - ophthalmology
            RT - nursing

S - Agriculture

T - Technology
            TA to TP - various engineering disciplines
            TR - photography

U - Military Science (for military history, see divisions D
            through F)

V - Naval Science

Z - Bibliography, Library Science