Note 6 — ARCHAIC MAN, FIRST SETTLER IN ILLINOIS (8000 to 2500 B.C.)[6]
Reading edition
These dates and those given hereafter refer to the earliest and latest sites known in Illinois for the cultures under consideration. Although supported by radiocarbon dating methods, they are only approximate. Undoubtedly also cultures in one area disappeared while they continued to flourish in another part of the state or in other states.