Probably from the resemblance of its leaves to the leaflets of the fronds of the maidenhair fern
Ginkgo - Maidenhair Tree.
From an evolutionary point of view, it is of interest to note the occurrence of filicinean and cycadean characters in the maidenhair tree.
The maidenhair tree is one of the most interesting survivals from the past; it represents a type which, in the Palaeozoic era, may have been merged into the extinct class Cordaitales.
The Cordaitales (see Palaeobotany: Palaeozoic) are represented by extinct forms only, which occupied a prominent position in the Palaeozoic period; these plants exhibit certain features in common with the living Araucarias, and others which invite a comparison with the maidenhair tree (Ginkgo biloba), the solitary survivor of another class of Gymnosperms, the Ginkgoales (see Palaeobotany: Mesozoic).