12 May 1995
Vol 268, Issue 5212

About The Cover

This skeleton of a Late Triassic turtle (210 million years ago) from Argentina extends the South American fossil record of turtles by 60 million years and provides the basis for a new interpretation of basal turtle relationships and the origin of living groups. This new taxon along with those from Northern Hemisphere sites suggest that turtles were a taxonomically and ecologically diverse group by the Late Triassic. The shell is 55 centimeters long from front to back. See page 855. [Photo: G. W. Rougier]