C. fragilis is a perennial fern which will often be found growing from cracks in walls and rocks, particularly basic rocks. The spores are rounded and covered in an inflated bladder like bag (indusium). Hence the "Bladder" fern.

This a fern which prefers the north and is abundant throughout Scotland. It is also easily found in Wales but less frequently found in England particularly in the southern counties. It is common in north west Ireland.

Irwell vale Bridge, Lancashire 7th June 2007

Added on January 23rd 2005, updated 10th December 2008, updated 21st March 2010