FJCUS SEREATUS. 



47 



capital manure for land, it can be preserved, and 

 used as food for cattle, it can be made into kelp, 

 and it is an excellent substance in which to pack 

 lobsters, and other marine productions, that are 

 sent inland. The bladder-wrack is much used 

 for the same purpose, but its sliminess renders 

 it liable to heat and to ferment; while Fucus 

 serratus, being comparatively free from slime, 

 retains its cool dampness, and preserves the fish 

 sweet. It is really of importance, for a tainted 

 lobster is not only nauseous to the palate, but 

 even dangerous to the whole system. 



There is a very tiny fucus, some four or six 

 inches long at the most, that is to be found near 

 high water-mark, chiefly in summer and autumn ; 

 it may be recognised by a number of small 

 channels that furrow one side of the frond. It 

 has no air-vessels. 



All these plants, together with all the algae 

 comprised in this chapter, belong to the class of 

 algae called Melanosperms, or black-seeded; so 

 called from the dark olive tint of the spores, or 

 tiny seeds, from which they spring. They all 

 seem to be exclusively marine. 



At spring-tides the waters recede considerably 

 below their usual mark, and these seasons are 

 the harvest-times of the shore-naturalist. As 



