Lane affixed a label (usually paper) on to the bottom the boxes.  Although labels aren't on all boxes today, it is assumed all boxes had a label attached originally.  Labels appear on all box variations except all Short versions as the practice of including the label was discontinued in the late 1950's (around 1956-57) likely as a cost savings measure.  All messages begin with "Please Remember" but the wording of the paragraph that follows changes slightly over time as well as the border sometimes surrounding the paragraph.  In this area an image of all labels found thus far can be viewed along with what box variation they are found upon.   Bottom Labels, like other unique features, can be used to estimate the boxes' age or date of manufacture.  The labels below are loosely arranged from oldest to newest based upon several other factors like what boxes they appear upon.  However labels appear to change more often than other features making them difficult to put into exact order