It may further be mentioned that the psilotaceae, an isolated epiphytic family hitherto referred to the Lycopods, have been regarded by several recent authors as the last survivors of the Sphenophyllales, which they resemble both in their anatomy and in the position of their sporangia.
"Darwin and Modern Science"
A.C. Seward and Others
Anatomically some relation to the Sphenophylls is indicated, and perhaps the recent psilotaceae give some support to this connection, for while their nearest alliance appears to be with the Sphenophylls, they approach the Lycopods in anatomy, habit, and mode of branching.
"Darwin and Modern Science"
A.C. Seward and Others