Long Lasting Rock Groups From The 1960s

Listening to the CLASSIC ROCK channel of the MUSIC CHOICE collection has reminded me of the many ensembles that imitated the Beatles--such as Herman's Hermits and its THERE'S A KIND OF HUSH, ALL OVER THE WORLD TONIGHT--; and how most of said ensembles closed shop after a few years.
Which groups of the 1960s are still around? There are the Rolling Stones, Fleetwood Mac, Grateful Dead, and the Who; are there any others? Am I right in assuming that there aren't this many? (Hijo del Cid holds up the fingers of both his hands)