Pellaea is a genus of 80 species mostly from South America and Africa. You should place them in a dry place and with plenty of drainage.
P.atropurpurea produced fronds which grow between 4 to 12 inches.
P.falcata generally has longer fronds between 6 and 18 inches.
P. rotundifolia, the button fern, is shown below.
The compost they are planted in should be composed of 2 parts peat, 1 part loam with coarse sand. Plant them in well-drained pots and place them in a well-lit part of your greenhouse.