When thus annexed, however, a district may, according to the recent "Insular Cases," find itself, or by subsequent statute be placed, in any one of the following categories.

1. A State of the Union.

2. A "Territory" incorporated into the Union. This Territory may be either "unorganized," as for example is Alaska, or "organized," examples of which are at present New Mexico, Arizona and Hawaii.

3. A Territory appurtenant to, that is, subject to the sovereignty of the United States, but not "incorporated," constitutionally speaking, into the Union of States and Territories for the benefit and protection of whose inhabitants the Constitution was adopted.