 He believed it belonged to a bird more primitive than "Archaeopteryx", and assigned it to its own sublcass (Praeornithes), order (Praeornithiformes) and family (Praeornithidae).However, in 1986, Bock published a paper arguing that the "feather" was in fact the leaf of a cycad.This opinion was followed by Doludenko and colleagues in 1990, who noted that it was similar to the leaves of the cycad species "Paracycas harrisii".