Plate XL VI. 
Fig. 209. DUMONTIA FILIFORMIS. 
Colour. Dull purple ; fading to green and yellow. 
Suhstance. Gelatinous ; membranaceous ; tender ; very slippery to the touch. 
Character of Frond. A simple stem, finely drawn out and tapering to each end (attenuated) ; 
furnished with long, simple, alternate branches, attenuated in the same manner. Both 
stem and branches cylindrical and tubular ; filled with a watery jelly. 
Measurement. Stem sometimes from 8 to 18 inches long, with branches from 4 to 5. In other 
specimens the stem is very short (from 2 to 3 inches) ; and the branches from 10 to 
14. In others there is scarcely any stem at all. In others the whole plant is small 
and thread-like (filamentous). 
Fructification. Of two kinds. 1. Eonndish masses of spores (favellce) immersed in the sub- 
stance of the frond. 2. Tetraspores imbedded beneath the same ; scattered over the 
branches. Visible like dark dots through. 
Habitat. Our coasts generally. On rocks, &c. at half- tide level. Common. 
Fig. 210. NEMALEON MULTIFIDUM. 
Colour. Dull purple, or purplish-brown. 
Suhstance. Gelatinous ; solid ; very elastic ; firm. 
Character of Frond. Cylindrical, about the thickness of a crow’s quill ; once or twice forked, 
distantly ; or simple ; or irregularly, slightly branched. Axils rounded and clumsy. 
Measurement. From 3 to 6 inches long. 
Fructification. Only one kind known. Globular masses of spores attached to the filaments 
which form the outer layer of the frond. Visible like dark dots through. 
Habitat. Our coasts generally in the warmer stations. Common along the western shores of 
Scotland and Ireland. On rocks and shells near low-water mark in exposed situations. 
Not unfrequent. 
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