Plate XXII. 



Fig. 95. ECTOCARPUS GRANULOSUS. 



Coloitr. Grreen in youth; afterwards olive-green or yellowish. 

 Substance. Moderately firm; soft. 



Character of Frond. Feathery tufts of jointed threads {filaments). Filaments much 

 branched. Branches on each side stems; sometimes opposite, sometimes alter- 

 nate; extreme branchlets often set, four or five in succession on one side (secund). 

 Main divisions slightly entangled; lesser ones quite free and feathery. 



Measurement. From 1 inch to a foot long. (Dependent on the depth of water.) 



Fructification. External seeds (spores) borne on the branchlets. Spores large; oval; 

 dark-brown; marked with lines across {transversely striate)-, minutely cross- 

 barred; unstalked (sessile); abundant. 



Habitat. Our shores generally. On rocks or algje between tide-marks. Frequent. 



The figure of this plant is not very characteristic. Its growth is looser and 

 freer than the representation. There are several varieties of it, one of which 

 is now raised to the dignity of a species, E. tesselatus. It is a small plant, 

 growing in crevices of the rocks at half-tide level, and is exquisitely green when 

 young. The tesselated appearance of the spores gave rise to the name. One of 

 its characters is the secund growth of the extreme branchlets. Another variety, 

 chiefly found on the south coast, is less richly branched, but all, or nearly all its 

 branches and branchlets are opjjosite on each side the stems. Intermediate forms 

 occur with opposite and alternate branching mixed. E. tesselatus was first noticed 

 on rock-crevices on the top of Filey Bridge by Mr. Hayden; but it has been found 

 abundantly since. "Whether it has a right to a position as a species is still 

 doubtful, but it is at any rate a very lovely variety. 



Fig. 96. ECTOCARPUS MERTENSII. 



Colour. A beautiful olive-green in the early part of the year, becoming browner in 

 the summer and autumn. 



Substance. Soft and dehcate. 



Character of Frond. Tufts of jointed threads (filaments). Filaments branched in 

 a regular and remarkable manner. Main stems simple, or nearly so; set 

 throughout with exactl}^ opposite branches, of unequal length. Branches also 

 simple; set throughout (and closely) with slender, spreading branchlets i the 

 diameter of the branch; except where a pair of larger branchlets takes the 

 place of a pair of the lesser ones. Secondary branchlets similarly re-branched; 

 the whole plant resembling a collection of delicate feathers. 



Measurement. From 2 inches to a foot in leng-th. 



Fructification. Seeds (spores) imbedded in the branchlets, forming dark oblong 

 swellings. (See figure.) 



Habitat. Our coasts here and there from Orkney to Cornwall, and in Ireland. On 

 mud-covered rocks and stones, near low-water mark; and at a greater depth. 

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