THE HALF-TIDE POOL. 59 



Gtkiffithsia Setace^: (Bristle-like Grifiithsia). — 

 Hanging from the shadowy side of a rock or in a 

 mid-tide pool, in tufts from three to six inches long, 

 colour deep crimson, and slightly branched, or rather 

 forked. On immersing it in fresh water, the mem- 

 brane bursts with a crackling noise, and the colouring 

 is lost : like several others of the genus, it stains paper 

 of a bright carmine, which remains unaltered for years. 

 This seaweed requires mounting as soon as possible, 

 for it soon changes colour, and becomes yellowish. 

 Keep it in sea tvate?*, dark and cool. 



The fructification is a beautiful microscopic object. 

 With quite a low power we see the tuft of little ramuli 

 at the end of a branch, within which are tetraspores, 

 cells full of crimson spores, or else we find on naked 

 ramuli two larger cells or favellce full of minute red 

 spores. There is a third kind of fructification some- 

 times found in the tufts which bear the tetraspores, 

 called antheridia — minute oval bodies, composed of 

 dense whorls of glossy threads, not perfectly under- 

 stood. This plant, delicate as it is, may be kept in 

 sea water, for many months preserving its colour and 

 fruit. A glass bottle sealed up will not require changing 

 for a year, and gives an interesting object as a seaside 

 remembrance. 



Geiffithsia Coeallik^. — "We only find this in 

 deep pools, usually on the shady side or under other 

 seaweed near low- water mark. It is jointed like a 

 coralline, but of a rich crimson, and may be known by 

 its strong disagreeable smell, especially when brought 

 home and immersed in fresh water ; it then discharges 



