Fig. 11. FUCUS CERANOIDES. 



Colour. A fine olive; clear. Becoming darker^ but not blacky wken dry. 



Substance. Much less leathery and tough than its relatives {congeners). 

 Described as coriaceo-memhranaceoits ; i. e. leathery thin-skin^ or thin- 

 skinned leather! 



Character of Frond. Flat^ with clearly marked line of midrib; branched. 

 Branching partially forked [sub-dlchotomous) . Side branches alternate^ 

 then diverging into several forkings. Width very variable. Margins 

 smooth [entire). 



Measurement. From 1 to 2 feet long. 



Air-vessels. None : though a tendency to inflation in the axils of the upper 



forkings is often perceptible. 

 Fructification. Minute seeds [spores) in special receptacles at the ends of the 



branches. Eeceptacles oval; a couple often forming the last forking; 



smaller than those of F. vesiculosus ; orange-coloured^ slimy, tubercled, 



but not so coarsely as those of F. v. 

 Habitat. Our shores generally; but not so common as the rest of the family. 



On rocks and stones between tide-marks; chiefly in places where rivers 



or other fresh waters run into the sea. Occasionally even in brackish 



water. 



A very beautiful variety among the coarse Melanosperms, and an interesting 

 plant to look for, from its not being so common as its brethren, and its greater 

 refinement of appearance. It has been found thrown ashore at Filey. 



Fig. 12. FUCUS SEREATUS. 



Colour. A fine dark olive-green; glossy; retaining both its clearness and 



colour when dry. 

 Substance. Tough, leathery. 



Character of Frond. Flat, midribbed, branched. Branching repeatedly forked 

 [dichotomous) . Width very variable. Margins always toothed like a 

 saw [serrated), but more or less deeply so in difi'erent specimens. 



Measurement. From 2 to 6 feet long; width very various. 



Air-vessels. None. 



Fructification. Minute seeds [spores) in special receptacles at the ends of the 

 branches. Receptacles narrow-oval; flattish; not extending to the mar- 

 gins, which retain the notched [serrated) character of the rest of the frond. 



Habitat. Our rocky shores generally. At half -tide level; very common. 

 The notched margins of this plant make it very easy of detection. 



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