Roman Catholics are more numerous than all the Protestant sects taken together, having in 1906 a membership of 113,419 out of a total of 212,988 in all denominations. In the last decade of the 19th century the urban population (i.e. population of places having 4,000 inhabitants or more) increased from 226,268 to 251,685, or 11.2%; the semi-urban population (i.e. population of incorporated places, or the approximate equivalent, having less than 4,000 inhabitants) increased from 14,221 to 26,674, or 87.5%; while the rural population (i.e. population outside of incorporated places) decreased from 420,597 to 416,134, or 1%. The principal cities of the state are: Portland, pop. (1910), 58,571; Lewiston, 26,247; Bangor, 24,803; Biddeford, 17,079; Auburn, 15,064; Augusta (the capital), 13,211; Waterville, 11,458; Bath, 9,396; Westbrook, 8,281; and Rockland, 8,174. _Administration._--Maine has had but one state constitution; this was ratified in December 1819, about three months before the admission of the state into the Union. It admits of amendment by a two-thirds vote of both houses of the legislature followed by a majority vote of the electorate at the next September election; or, as provided by an amendment adopted in 1875, the legislature may by a two-thirds vote of each house summon a constitutional convention. From 1819 to 1875 twelve amendments were adopted; in 1875, after nine more were added, the twenty-one were incorporated in the text; and between 1875 and 1899 nine more were adopted. Suffrage is conferred by the constitution on all male citizens of the United States who are at least twenty-one years of age and have, for some other reason than because of being in the military, naval or marine service of the United States, or of being students at college, lived in the state for three months next preceding any election; the following classes, however, are excepted: paupers, persons under guardianship, Indians not taxed, and, as provided by an amendment adopted in 1892, persons intellectually incapable of reading the state constitution in the English language or of writing their names. State elections were annual until 1897 when they were made biennial; they are held on the second Monday in September in even numbered years, Maine being one of the few states in the Union in which they are not held in November.