again in 1864 and 1866 by the eastward extensions of the boundaries of the State of Nevada and in 1868 by the organization of Wyoming Territory. Utah was admitted to the Union in 1896 as the forty-fifth State with boundaries as at present.

Vermont.-Vermont was admitted to the Union in 1791 as the fourteenth State and was the first to be admitted after the adoption of the Constitution by the Thirteen Original States.

Virginia.-Virginia, one of the Thirteen Original States, included in 1790 the areas now constituting the States of Kentucky and West Virginia. The area of the State was reduced in 1791 by the formation of the District of Columbia and in 1792 by the admission of Kentucky into the Union as a separate State; the area was enlarged in 1846 by the retrocession of the part of the District of Columbia south of the Potomac but was further reduced in 1863 by the admission of West Virginia into the Union as a separate State. In 1866 two additional counties (Berkeley and Jefferson) were annexed to West Virginia, leaving the boundaries of Virginia as at present.

Washington.-Washington was organized as a Territory in 1853 from part of Oregon Territory, and included an area now comprising the State of Washington, northern Idaho, and part of Montana. In 1859, upon the admission of Oregon as a State, the remaining portion of Oregon Territory, comprising the rest of Idaho and parts of Montana and Wyoming, was added to the Territory of Washington. The area of the Territory was reduced to the present limits of the State in 1863, upon the organization of Idaho Territory. Washington was admitted to the Union in 1889

as the forty-second State.

West Virginia.-West Virginia, formed from 48 counties of Virginia, was admitted to the Union in 1863 as the thirty-fifth State. In 1866, with the annexation of two additional counties (Berkeley and Jefferson) from Virginia, the boundaries were established as at present.

Wisconsin.-Wisconsin was organized as a Territory in 1836 from that part of Michigan Territory which lay west of the present limits of the State of Michigan. As originally constituted, the Territory included the present States of Wisconsin, Iowa, Minnesota, the eastern parts of North and South Dakota, and a small part of Nebraska. In 1838 that part of the Territory lying west of the Mississippi River and a line drawn due north from its source to the Canadian boundary was organized as the Territory of Iowa. In 1848 that part of the Territory lying within the present boundaries of the State was admitted to the Union as the thirtieth State.

Wyoming.-Wyoming was organized as a Territory in 1868 with boundaries as at present from parts of Dakota, Idaho, and Utah Territories. It was admitted to the Union in 1890 as the forty-fourth State.

Territories

The circumstances under which the Territories were acquired by the United States and the dates of their acquisition are as follows:

Alaska. Alaska was acquired by purchase from Russia in 1867 and was organized as a Territory in 1912.

Hawaii.—Hawaii, by voluntary action of its people, ceded its vereignty to the United States in 1898 and was organized as a Territory on June 14, 1900.

Possessions

The circumstances under which the principal possessions were acquired and the dates of their acquisition are as follows:

American Samoa.-American Samoa was acquired by the United States in accordance with a convention between the United tates, Great Britain, and Germany, signed December 2, 1899, ratified February 16, 1900, and proclaimed by the President of the United States on the latter date. Under an Executive order

of February 19, 1900, the islands were placed under the authority of the Secretary of the Navy for use as a naval station. The high chiefs of the Tutuila voluntarily ceded the islands of Tutuila and Aunuu to the United States on April 17, 1900; and the islands of the Manua group (Tau, Olosega, and Ofu) were ceded by their high chiefs on July 16, 1904. By joint resolution of Congress, approved March 4, 1925, Swains Island was annexed to American Samoa.

Guam.—The island of Guam was ceded by Spain to the United States under the terms of the Treaty of Paris, signed December 10, 1898, and ratified in the following year.

Puerto Rico.-The island of Puerto Rico was formally surrendered by Spain to the United States in October 1898, and was ceded to the United States, together with Vieques, Culebra, and other small adjacent islands, by the Treaty of Paris, signed December 10, 1898, and ratified in the following year.

Virgin Islands of the United States.-The Virgin Islands of the United States, formerly known as the Danish West Indies, were acquired by the United States by purchase from Denmark in 1917, the formal transfer of possession having taken place on March 31 of that year. St. Croix, St. John, and St. Thomas are the 3 principal islands of the group, although there are 65 smaller islands, most of which are uninhabited.

Other Areas

The circumstances under which the Canal Zone came under the jurisdiction of the United States and the Trust Territory of the Pacific Islands came under the trusteeship of the United States are as follows:

Canal Zone. The use, occupation, and control of the Canal Zone were granted to the United States under the terms of a treaty with the Republic of Panama, signed November 18, 1903, and ratified in the following year.

Trust Territory of the Pacific Islands.-The United States became the administering authority over the Trust Territory of the Pacific Islands (which comprises the Caroline, Marshall, and Marianas Islands except Guam) under an agreement approved by the Security Council of the United Nations on April 2, 1947, and by the United States Government on July 18, 1947. By Executive order, the military government in these islands was terminated on the latter date, and the authority and responsibility for the civil administration were delegated to the Secretary of the Navy.

URBANIZED AREAS

Definition

"Urbanized areas" have been defined for the first time in the 1950 Census. The major objective of the Bureau of the Census in delineating these areas was to provide a better separation of urban and rural population in the vicinity of our larger cities than was possible under the old definition. All persons who resided in urbanized areas on April 1, 1950, are included in the urban population according to the new definition. The effect of the adoption of the urbanized area concept was to include in the urban population 6,203,596 persons living under distinctly urban conditions in the immediate environs of our larger cities who under the old definition would have been included in the rural population. (See table E.)

An urbanized area is an area that includes at least one city with 50,000 inhabitants or more in 1940 or later according to a special census taken prior to 1950 and also the surrounding closely settled incorporated places and unincorporated areas that meet the criteria listed below. Since the urbanized area outside of incorporated places was defined on the basis of housing or population density or of land use, its boundaries for the most part are not political but follow such features as roads, streets, railroads, streams, and other clearly defined lines which may be easily identi fied by census enumerators in the field. The urbanized area

boundaries were selected after careful examination of all available maps, aerial photographs, and other sources of information, and then were checked in detail in the field by trained investigators to insure that the criteria were followed and that the boundaries were identifiable.

The delineation of the boundaries of the urbanized areas had to be completed prior to the beginning of enumeration; consequently, it was not possible to establish urbanized areas in connection with those cities which attained a population of 50,000 or more according to the 1950 Census. Urbanized areas were established for Fort Smith, Ark., and Muskegon, Mich., both of which had in excess of 50,000 inhabitants according to special censuses conducted prior to 1950. The population of both of these cities fell below 50,000 in 1950. The urbanized areas defined for these two cities, however, were retained in the tabulations.

The urban fringe of an urbanized area is that part which is outside the central city or cities. The following types of areas are embraced if they are contiguous to the central city or cities or if they are contiguous to any area already included in the urban fringe:

1. Incorporated places with 2,500 inhabitants or more in 1940 or at a subsequent special census conducted prior to 1950.

2. Incorporated places with fewer than 2,500 inhabitants containing an area with a concentration of 100 dwelling units or more with a density in this concentration of 500 units or more per square mile. This density represents approximately 2,000 persons per square mile and normally is the minimum found associated with a closely spaced street pattern.

3. Unincorporated territory with at least 500 dwelling units per square mile.

4. Territory devoted to commercial, industrial, transportational, recreational, and other purposes functionally related to the central city.

Also included are outlying noncontiguous areas with the required dwelling unit density located within 11⁄2 miles of the main contiguous urbanized part, measured along the shortest connecting highway, and other outlying areas within one-half mile of such noncontiguous areas which meet the minimum residential density

rule.

Although an urbanized area may contain more than one city of 50,000 or more, not all cities of this size are necessarily central cities. The largest city of an area is always a central city. In addition, the second and third most populous cities in the area may qualify as central cities provided they have a population of at least one-third of that of the largest city in the area and a minimum of 25,000 inhabitants. The names of the individual urbanized areas indicate the central cities of the areas.

Population of Urbanized Areas

Somewhat less than one-half of the total, and more than seventenths of the urban, population of the United States was living in the 157 urbanized areas in 1950 (table 5a). Of the 69,249,148 persons living in the urbanized areas, 48,377,240 were in the 172 central cities and 20,871,908 were living in the urban-fringe areas. In urban-fringe areas, there were 12,949,890 persons living in 859 incorporated places of 2,500 inhabitants or more, 577,992 persons living in 457 incorporated places under 2,500 inhabitants, and 7,344,026 persons living in unincorporated territory. The number of persons in the incorporated places under 2,500 inhabitants and in unincorporated territory-7,922,018-represents the persons in urban territory living outside urban places, and, consequently, the net addition to the urban population attributable to the urbanized area delineations.

In population, the urbanized areas ranged in size from the Fort Smith Urbanized Area, which had a population of 56,046, to the New York-Northeastern New Jersey Urbanized Area, which had a population of 12,296,117 (table 18). The 12 urbanized areas with more than 1,000,000 inhabitants had a combined population of 37,817,068, or more than one-half the population of the 157

urbanized areas under 100,000 inhabitants represented less than 5 percent of the total population in urbanized areas.

Seven out of ten of the persons living in the urbanized areas were residents of the central cities. The proportion of the population of the urbanized areas living in the central city or cities, however, varied greatly among the areas, ranging from a low of 28.3 percent for the Wilkes-Barre Urbanized Area to virtually 100 percent for the Beaumont Urbanized Area. There were 79 urbanized areas with 80 percent or more of their population in the central city or cities. Only seven urbanized areas—the Boston, Los Angeles, Phoenix, Pittsburgh, Providence, San Bernardino, and Wilkes-Barre Urbanized Areas-had fewer than half of their inhabitants living in the central cities. (See table 17.)

Population Density

The population per square mile of land area for all 157 urbanized areas was 5,438 (table 17). Three of the areas-the New York-Northeastern New Jersey, Philadelphia, and Lancaster Urbanized Areas-had densities in excess of 9,000. Five-the Atlantic City, Duluth-Superior, Fort Smith, St. Petersburg, and Sioux City Urbanized Areas-had densities under 2,000. The density of the central cities was more than double that of the urban-fringe areas- -7,788 as against 3,200. In six of the areas, however, the Brockton, Fall River, Fort Smith, Los Angeles, New Orleans, and Stamford-Norwalk Urbanized Areas, the density of the urban fringe exceeded that of the central city. The density in the central cities varied from 1,414 for Duluth-Superior to 24,537 for the three central cities of the New York-Northeastern New Jersey Urbanized Area. An even greater variation was found in the densities of the urban-fringe areas. In 11 areas the urbanfringe areas had densities in excess of 4,000. At the other extreme, the urban-fringe areas of Beaumont and Amarillo had densities of 29 and 179, respectively. These and other low densities in urban-fringe areas are attributable to the inclusion in the urbanized areas of land devoted to urban uses, such as industrial areas, railroad yards, and airports, which had little or no residential population.

COUNTIES

Definitions

The primary divisions of the States are, in general, termed counties; but in Louisiana these divisions are known as parishes. There are also a number of cities which are independent of any county organization and thus constitute primary divisions of their States, namely, Baltimore in Maryland, St. Louis in Missouri, and 27 cities in Virginia. The District of Columbia, which is not divided into counties, is included here as the equivalent of a county as are also the three parts of Yellowstone National Park in Idaho, Montana, and Wyoming. There were 3,070 counties and parishes in continental United States in 1950 and 33 county equivalents. The number of counties remained unchanged between 1940 and 1950. Washington County, S. Dak., was annexed by Shannon County. Offsetting this loss, however, was the organization of a new county, Los Alamos, in New Mexico. The number of county equivalents increased by three three cities in Virginia, Colonial Heights, Falls Church, and Waynesboro, became independent of county organization during the decade. Changes in the number of counties were fairly frequent some decades ago but have become progressively rarer. These changes, as well as changes of county boundaries, are listed in the notes to tables 5 and 6 of the State chapters and in the reports of other censuses.

Population of Counties

The counties ranged in population from Armstrong County, S. Dak., which had 52 inhabitants, to Cook County, Ill., which had 4,508,792 inhabitants. Ten additional counties (Los Angeles, Calif.; Middlesex, Mass.; Wayne, Mich.; Bronx, Kings, New York, and Queens, N. Y.; Cuyahoga, Ohio; Allegheny and Philsdelphia, Pa.) had 1,000,000 inhabitants or more. These 11

16

Onslow, N. C..

42, 047

17,939

24, 108

134.4

17

Orange, Texas.

40, 567

17,382

23, 185

133.4

18

Anderson, Tenn.

59, 407

26, 504

32, 903

124.1

19

20

Midland, Texas.

Includes 3,070 counties; Baltimore city, Md.; St. Louis city, Mo.; the District of Columbia; 27 independent cities in Virginia in 1950 and 24 in 1940; and the parts of Yellowstone National Park in Idaho, Montana, and Wyoming.

Trends in Population, 1940 to 1950

Despite the record gain of 19,000,000 in the population of the United States as a whole, nearly one-half of the counties lost population and nearly one-fourth lost 10 percent or more (table 20). Of the 3,103 counties and county equivalents, 1,518, or 48.9 percent, lost population, and 708, or 22.8 percent, lost 10 percent or more. Of the 1,585 counties which gained population, 884, or 28.5 percent of the counties, increased by 10 percent or more and 520, or 16.8 percent, increased by 20 percent or more. More than four out of every five counties in the Northeast, and more than three out of every five counties in the West, increased in population. In both the North Central States and the South, more than half the counties lost population. Connecticut, Delaware, and Rhode Island, all of which have relatively few counties, were the only States in which all counties increased in population.

Thirty-one counties and the independent city of Falls Church, Va., more than doubled in population between 1940 and 1950 (table J). All but one of these counties-Grant County, Kans.were located in the South or in the West. Twelve of these counties and Falls Church city were in the South Atlantic States and seven in the Pacific States.

The fastest growing county in the United States between 1940 and 1950 was Warwick County, Va., which had a population increase of 331.2 percent. At the other extreme, the largest percentage decline was experienced in Esmeralda County, Nev., which had a decline of 60.5 percent.

Counties in Alaska, Hawaii, and Puerto Rico

Alaska, Hawaii, and Puerto Rico are also divided into counties or county equivalents. Alaska is divided into 4 judicial divisions; Puerto Rico is divided into 77 municipalities; Hawaii is officially

1 Independent city.

Table 19 presents the 1950 and 1940 population of the counties in continental United States, Alaska, Hawaii, and Puerto Rico, together with the rate of change for the decade.

MINOR CIVIL DIVISIONS

Definitions

To the primary political divisions into which counties are divided, the Bureau of the Census applies the general term "minor civil divisions." In addition to the county divisions shown by the Bureau, there are thousands of school, taxation, election, and other units for which separate census figures are not published. Where more than one type of primary division exists in a county, the Bureau of the Census uses the more stable divisions, so as to provide insofar as possible comparable statistics from decade to decade.

Changes in Units, 1940 to 1950

The minor civil divisions shown for the State of Washington in previous censuses were the election precincts, a few townships, and some of the cities and towns. The election precincts are not suitable for statistical purposes because their boundaries change so frequently as to prevent comparisons of data from one period to another. Accordingly, the minor civil divisions were replaced in the 1950 Census by "census county divisions," which are newly established special areas which will remain as relatively permanent statistical areas corresponding to the minor civil divisions in other States.

The census county divisions were defined by the State Census

Bureau of the Census and were reviewed by interested State and local groups, the Bureau of Agricultural Economics, United States Department of Agriculture, and by the Bureau of the Census.

A total of 642 census county divisions was established in the State. Each incorporated place with a population of 2,500 or more, according to a 1948 estimate of the Washington State Census Board, was made a separate census county division, and each incorporated place of 10,000 inhabitants or more which was not divided into census tracts was divided into census county subdivisions. The census tracts in the adjacent areas of Seattle and Tacoma outside incorporated places of 10,000 inhabitants or more are recognized as census county divisions.

The minor civil divisions shown for Florida in previous censuses were election precincts. The boundaries of election precincts, however, have been subject to frequent changes. In the 1950 Census, therefore, the election precincts were replaced by another division of the counties, the commissioner's districts, the boundaries of which are less subject to change.

Number and Types of Minor Civil Divisions

There were 48,529 minor civil divisions or their equivalents recognized by the Bureau of the Census in continental United States on April 1, 1950. The most numerous of the minor civil divisions were the civil and judicial townships, which numbered 20,879 and were found in 20 States. The total also included 8,708 precincts, 6,739 districts, and 4,326 independent municipalities, and 3,599 towns. The remaining minor civil divisions are known as beats, gores, grants, islands, purchases, surveyed townships, etc., some of which are found only in a single State. The number and types of minor civil divisions in each State are shown in table 21. For the number and types of minor civil divisions in each State in 1940, see reports of the Sixteenth Census (1940), Areas of the United States: 1940, U. S. Government Printing Office, Washington, D. C., 1942, p. 5.

Minor Civil Divisions in Alaska, Hawaii, and Puerto Rico

The 4 judicial divisions in Alaska are divided into 46 recording districts. The 5 counties in Hawaii are divided into 28 judicial districts. The 77 municipalities in Puerto Rico are divided into 943 barrios, including those in cities, towns, and villages.

INCORPORATED AND UNINCORPORATED PLACES

Definitions

Al

The term "place" as used in reports of the 1950 Census refers to a concentration of population, regardless of the existence of legally prescribed limits, powers, or functions. Most of the places listed are incorporated as cities, towns, villages, or boroughs, however. In addition, the larger unincorporated places outside the urbanized areas were delineated and those with a population of 1,000 or more are presented in the same manner as incorporated places of equal size. Each unincorporated place possesses a definite nucleus of residences and has its boundaries drawn so as to include, if feasible, all the surrounding closely settled area. though there are unincorporated places in the urban-fringe areas, it was not considered feasible to establish boundaries for such places and therefore they were not identified as separate places. Political units recognized as incorporated places in the reports of the 1950 Census are those which are incorporated as cities, boroughs, towns, and villages with the exception that towns are not recognized as incorporated places in the New England States, New York, and Wisconsin. The towns in these States are minor civil divisions similar to the townships found in other States and not necessarily thickly settled centers of population such as the cities, boroughs, towns, and villages in other States. Similarly, in those States where some townships possess powers and functions similar to those of incorporated places, the townships are not classified as "incorporated places." Thus some minor civil

are not regarded by the Census Bureau as "incorporated places." Without this restriction all of the towns in the New England States, New York, and Wisconsin and the townships in States such as New Jersey would have to be counted as incorporated places without any consideration of the nature of population settlement. The densely settled portion of a town or township in these States, however, may be recognized by the Bureau of the Census as an unincorporated place (or as part of an urban fringe). Relationship Between Incorporated Places and Counties

In most States the incorporated places form subdivisions of the minor civil divisions in which they are located. In other States, however, all or some of the incorporated places are also minor civil divisions. St. Louis, Baltimore, and 27 cities in Virginia are independent of any county organization. In a number of instances, such as Philadelphia, San Francisco, and Denver, the incorporated place is coextensive with the county in which it is located. New York City, on the other hand, is made up of five counties.

Table 23 presents the population of cities having 100,000 inhabitants or more in 1950, with comparative figures going back to the first census in which the city appears. There were 106 cities of 100,000 inhabitants or more in continental United States in 1950, whereas in 1940 there were only 92 cities of this size. The population of Lowell, Mass., dropped below 100,000 in 1950, and there were 15 cities the population of which passed 100,000. Nine of these cities were in the South, three in the West, two in the Northeast, and one in the North Central Region.

There were 44,311,617 persons living in the 106 cities of 100,000 inhabitants or more in 1950. This total represents an increase of 6,323,628, or 16.6 percent, over the 37,987,989 persons living in the 92 cities of this size in 1940 (table 5b). The largest numerical increase among cities of this size was experienced in Los Angeles, which had a gain of 466,081. The next largest increase was recorded in New York City, which experienced a gain of 436,962. The large percent increase in Baton Rouge is attributable in great