Habit and Detached Pinna with Involucre of Hymenophyllum Unilaterale Small 214×320 Medium 428×640 Large 685×1024 Download Tiff Original 1605×2400 | (412.4 KB) Description The common name of hymenophyllum is filmy fern. The unilaterale variety has dark green, rigid fronds. This fern is native to Great Britain. Keywords fern, filmy fern, Great Britain, hymenophyllum, hymenophyllum unilaterale, involucre, pinna Galleries Ferns Source: Nicholson, George The Illustrated Dictionary of Gardening, Div. VI (London, England: L. Upcott Gill, 1884)
