- Myelopteris topekensis, n. spD. P. Penhallow
- Contributions to the Pleistocene flora of CanadaD. P. Penhallow
- Notes on Devonian plantsD. P. Penhallow
- Two species of trees from the post-glacial of IllinoisD. P. Penhallow
- Report on tertiary plants of British Columbia collected by Lawrence M. Lambe in 1906, together with a discussion of previously recorded tertiary florasD. P. Penhallow