Quite an imagination those ancestors of ours had.

Looks like the (endogenous DMT?) sightings started a little earlier than the 1940's :p
Click here to see more UFO Artwork through history
with information on each work

[This page needs an update, cave art includes all kinds of shamanistic visionairy images not just limited to ufo & alien
(read: therianthropic=man-beast images) images. As soon as I find online images to link or post here I will perform the update.
More proof of the shamanistic origins of religion, for more information read Graham Hancock's book Supernatural
for an extensive overview of shamanistic cave-art.]