The Sporangia of a Fern
- Photographic study by Wan Yu of the reproductive structures of the Holly Fern.
- http://www.microscopy-uk.org.uk/mag/artjan02/wyufern.html

Polystichum setiferum
- Several photographs of Soft Shield Fern and the identifying features of the plant.
- http://www.plant-identification.co.uk/skye/aspidiaceae/polystichum-setiferum.htm

Polystichum aculeatum
- Several photographs of Hard Shield Fern and its identifying features.
- http://www.plant-identification.co.uk/skye/aspidiaceae/polystichum-aculeatum.htm

Polystichum lonchitis
- Several photographs of Holly Fern and the identifying features of the plant.
- http://www.plant-identification.co.uk/skye/aspidiaceae/polystichum-lonchitis.htm

Polystichum braunii
- image
- http://www.nic.funet.fi/pub/sci/bio/life/plants/pteridophyta/pteropsida/dryopteridaceae/polystichum/braunii.jpg