CollectA Williamsonia TreeCollectA Williamsonia Tree CollectA Model 89400 Product Dimensions: 12. 5 x 7. 5 cm Age: 3 years and up Williamsonia was a genus of prehistoric plants that belonged to the group of seed ferns known as Bennettitales. These plants thrived during the Mesozoic era, particularly during the Jurassic and Cretaceous periods. Unlike modern ferns, which reproduce with spores, Williamsonia reproduced with seeds! These plants had unique, flower like reproductive