HYMENOPHYLL UM. 



309 



peculiar in its habit of growth and general aspect. It has very little of the 

 appearance of a Hymenophyllum, as its dehcately-transparent, seaweed-like 

 fronds, which are produced from slender, creeping rhizomes (prostrate stems), 

 are simple (undivided), broadly spear-shaped and slightly sinuated (wavy- 

 margined) ; they are from Sin. to 5in. long, lin. to IJin. broad, borne on 

 slender, naked stalks 3in. to Gin. long, and are most interesting on account 

 of their venation, their simple (unbranched) and prominent veins reaching from 

 the mid vein to the margin at regular intervals. The sori (spore masses), six 

 to twelve on each side of the frond, are disposed 

 at the summit of the sinuations, their wedge-shaped 

 base being sunk in the frond. Another peculiarity 

 of this species, which greatly adds to its beauty, 

 is the brownish-rosy colour of the old fronds, 

 which remain on the plants for a very long time. 

 — Hooker, Species Filicum, i., p. 87, t. 31. Loive, 

 Ferns British and Exotic, viii,, t. 5a. 



H. demissum — de-mis'-sum (hanging down), 

 Swartz. 



This species, native of New Zealand, Fiji, Java, 

 and the Phihppine and adjacent Polynesian Islands, 

 is perhaps the most decorative and the easiest- 

 grown of the entire genus, and is so well appre- 

 ciated as to be found in every collection where an 

 attempt at the cultivation of Filmy Ferns is made. 

 Its fine fronds (Fig. 80), 4in. to 12in. long, Sin. 

 to 4in. broad, and broadly triangular, are borne on 

 upright, firm, wingless stalks 4in. to 6in. long and 



of a wiry nature ; they are three or four times divided nearly to the midrib, 

 and their lower leaflets, 2in. to oin. long, are cut down very nearly to the 

 rachis (stalk of the leafy portion) on both sides into numerous leafits, which 

 are again divided into pinnatifid segments. The sori (spore masses) are 

 very numerous (twenty to thirty to a leaflet), terminal and axillary on the 

 segments on both sides, and, provided with an involucre (covering) that 

 is divided nearly to the base and has egg-shaped, entire or toothed 



Fi^, 80, Frond and Portion of Rhizom6 

 of Hymenophyllum demissum 



(i nat. size). 



