Fig. 68. MYEIONEMA STRANGULANS. 



Colour. Dark-brown. 



Character of Frond. Minute; parasitic; forming a small, convex, dark -brown, dot- 

 like patch on a flat frond; a ring-like collar round a filiform one. Filaments 

 jointed. 



Measurement. A dot or an encircling patch, varying in extent. Filaments exces- 

 sively short. 



Fructification. Minute seeds (spores) nestling among the threads {filaments') of the 

 frond. 



Hahltat. Our coasts generally. On TJlvcs and FnteromorpluB. 



The dark-brown specks and bands formed by this plant on the green fronds 

 of Ulvce, &c., may easily be mistaken for symptoms of decay, if not carefully 

 examined. They consist of numerous short, upright, jointed threads, springing 

 from a thin expansion composed of decumbent ones. But it requires a micro- 

 scojoe and skill to find all this out. The general appearance is soon learnt. 



Fig. 69. MYRIONEMA LECLANCHERII. 



Colour. Olive. 



Character of Frond. Minute; parasitic; forming round, flat, olive-coloured patches 

 on the fronds of Hhodymenia palmata and JJlva latissima, making them look 

 as if spotted with decay. Filaments jointed. 



Measurement. The patches sometimes extend to J of an inch of diameter. Filaments 

 excessively short. 



Fructification. Minute seeds (spores) nestling among the threads {filaments) of the 

 frond. 



Habitat. Our shores generally. On Hhodymenia palmata; and on TJlva latissima, 

 in deep water. 



Thinner and lighter coloured than M. strangulans, and spreading in much 

 larger patches. 



Fig. 70. MYRIONEMA PUNCTIFORME. 



Colour. Dark-olive. 



Character of Frond. Minute; parasitic; convex; forming globose dots on Ceramium 

 ruhrum, &c. 



Measurement. A dot! 



Fructification. Minute seeds (spores) among the threads {filaments) of the frond. 

 Sahitat. Our coasts generally. On several red sea-weeds. 



Easily mistaken for little bits of dirt, unless examined. For another Myrionema 

 see Plate XVIII. Fig. 75. 



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