Create a dichotomous key for identification of the five preserved fern specimens:
Polystichum acrosticoides (Christmas fern)
Onoclea sensibilis (Sensitive fern)
Polypodium virginiatum (Rock polyploid)
Thelypteris noveborasensis (New York fern)
Osmunda cinnamomea (Cinnamon fern)
You can use any vegetative or reproductive structures. You should also use the frond type to differentiate between species.