Plate XVI. 



Fig. 65. ELACHISTA SCUTULATA. 



Colour. Dark brown. 



Substance. Soft; slippery feeling. 



Character of Frond. Dark, oblong, convex patcbes, densely clotbed witb very sbort 

 tbreads {filaments) ; parasitic on tbe receptacle tbongs of Himanthalia lorea. 

 Filaments jointed. 



Measurement. Patcbes, J an incb or more in lengtb. Filaments, J to J- incb long. 

 Fructification. Minute seeds (spores) concealed in tbe substance of tbe tubercle. 

 Habitat. Our coasts generally. On Himanthalia lorea. 



Tbese tubercles are formed of densely packed, branching fibres, wbence issue 

 filaments. They surround the Himanthalia tbongs, like dark warts; sometimes 

 completely covering them for tbe space of several inches ; very slippery to tbe 

 touch. 



Fig. 66. ELACHISTA PULVINATA. 



Colour. Olive. 

 Substance. Rather rigid. 



Character of Frond. Very minute globose tufts (rising from a tubercle); parasitic 

 on tbe fruiting branches of Cijstoseira ericoides. Tbreads (filaments) of the 

 tufts very short; tapering greatly to both ends; jointed. 



Measurement. About -^^ of an incb in diameter. 



Fructification. Minute seeds (spores) at the base of the threads. 



Habitat. South of England. West of Ireland. On Cijstoseira ericoides. 



A beautiful microscopic object, says Dr. Harvey. Ihe plant it infests looks 

 ■under a common lens as if spotted with minute hairy warts. It was first found 

 by Kiitzing. 



Fig. 67. ELACHISTA YELUTINA. 



Colour. Pale olive. 

 Substance. Soft; velvety. 



Character of Frond. Thin, irregular patches, clothed with very short threads (fila- 

 ments) ; parasitic on tbe 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 -^V inch 

 long. 



Fructification. Minute seeds (spores) stalked; at the base of tbe filaments. 

 Habitat. Our shores generally. On Himanthalia lorea. 



Difficult to distinguish from 1]. scutulata (with which it is often found) except 

 by the 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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