r 
Plate XVI. 
Fig. 65. ELACHISTA SCUTULATA. 
Colour. Dark brown. 
Substance. Soft ; slippery feeling. 
Character of Frond. Dark, oblong, convex patches, densely clothed with very short threads 
(filaments) ; parasitic on the receptacle thongs of Himantlialia lorea. Filaments 
jointed. 
Measurement. Patches, J an inch or more in length. Filaments, \ to ^ inch long. 
Fructification. Minute seeds (^sj)ores) concealed in the substance of the tubercle. 
Habitat. Our coasts generally. On Himantlialia lorea. 
These tubercles aie formed of densely packed, branching fibres, whence issue filaments. 
They surround the Himantlialia thongs, like dark warts; sometimes completely covering 
them for the si)ace of several inches ; very slippery to the touch. 
Fig. 66. ELACHISTA PULVINATA. 
Colour. Olive. 
Substance. Eather rigid. 
Character of Frond. Very minute globose tufts (rising from a tubercle) ; parasitic on the 
fruiting branches of Cystoseira ericoides. Threads {filaments) of the tufts very short ; 
tapering greatly to both ends ; jointed. 
Measurement. About -jL of an inch in diameter. 
Fructification. Minute seeds {spores) at the base of the threads. 
Habitat. South of England. West of Ireland. On Cystoseira ericoides. 
A beautiful microscopic object, says Dr. Harvey. The plant it infests looks under a 
common lens as if spotted with minute hairy warts. It was first found by Kiitzing. 
Fig. 67. ELACHISTA VELUTINA. 
Colour. Pale olive. 
Substance. Soft ; velvety. 
Character of Frond. Thin, irregular patches, clothed with very short threads {filaments) ; 
parasitic on the receptacle-thongs of Himanthalia lorea., and some say of Fucus 
serratus. Filaments very minute, one thickness throughout ; jointed. 
Measurement. Patches, J an inch or more in extent. Filaments, to inch long. 
Fructification. Minute seeds {spores) stalked ; at the base of the filaments. 
Habitat. Our shores generally. On Himanthalia lorea. 
Difficult to distinguish from E. scutulata (with which it is often found) except by tlie 
form of the spores which require microscopic examination. Nevertheless, the thin, velvety 
layer of this, and the wart-like prominence of the other, are always marks of distinction. 
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