Ferns of the Woods 



The Tunbridge Filmy Fern has fronds of an olive- 

 brown colour, in the wild state seldom more than 

 3 inches long, and appears to the casual observer as if 

 in a withered and dying condition. These fronds are 

 more or less distinctly divided into toothed and lobed 

 pinnae. 



To botanists it is known as Hymenophyllum Tun- 

 bridgense. The generic name is derived from two 

 Greek words, hymen, " a membrane," and phyllon, " a 

 leaf," which is evidently a reference to the texture of 

 the fronds. Tunbridgense is formed from Tunbridge, 

 and the fern is so-called because it was first recorded 

 from that district. 



The One-sided Filmy Fern is regarded by some 

 botanists simply as a subspecies of the former fern, but 

 the important points of distinction already referred to 

 appear to entitle this fern to the rank of a distinct 

 species. Then there are minor differences which are 

 also worthy of consideration. The fronds of the One- 

 sided Filmy Fern are coarser and of a darker hue 

 than the fronds of its near relative, and more able to 

 stand exposure to sunlight. The former fern, too, is 

 generally pinnate throughout, though occasionally only 

 pinnatifid at the top, with the pinnae lobed and toothed 

 on the side nearest the tip of the frond. The scientific 

 name of the One-sided Filmy Fern is Hymenophyllum 

 unilateral. Unilateral is a Latin word meaning " one- 

 sided," and the reason for its application to this fern has 

 already been stated. The word "filmy" is explained 

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