Petrified Forest National Monument, Ariz. It was thought that these were made by some form of insect (larvae) that had attacked the trees, and for purposes of identification they were described and named. Some time later Dr. Junius Henderson visited the Petrified Forest National Monument Museum, and
No takes yet. Share an insight, caveat, or question.
Myrl V. Walker (1938) studied this question.
Synapse has enriched 5 related papers. Consider them for comparative context: