Please give this page time to load.   The pictures below are of fly pupa and vary in age from 1 hour to 4 days old.

The lightest pupa (top left) has just been formed, the one to the lower left with the blackish tip is several hours old.  To the right is a reddish day old pupa.  The others vary in age from one to 4 days.

Notice the variations in color of the pupas.  Because of the color, it is difficult to see in manure or dirt.