GRACILLARIA. 197 



be noticed ; they are obscurely but perfectly veined, a faint 

 narrow midrib and lateral parallel veins may be distinctly 

 seen. 



GRIFFITHSIA, 



so named in honour of Mrs. Griffiths of Torquay, found on 

 the coast of Devonshire, and other parts of the southern 

 coast of England. The frond is rose-red, filamentous, and 

 jointed. The fructification of two kinds : 



1, Tetraspores affixed to whorled involucral ramuli or 

 small branches. 



2, Favellse, or gelatinous receptacles, surrounded by an 

 involucre, and containing a mass of minute angular spores. 



There is a beautiful species, called Griffithsia coraliiuz, 

 the filaments of which resemble a string of fine glossy 

 crimson beads, found on rocks at low-water-mark, or in 

 deep pools during Summer. This should be mounted, if 

 possible, with its tetraspores. 



GRACILLARIA, 



one of the Sphserococcoidse, named from a Latin word 

 signifying " slender." 



GraciUaria erecta is found on sand-covered rocks at 

 Sidmouth and Torquay ; it fruits in Winter,* when it should 

 be gathered and mounted ; for both kinds of fructification 

 are beautiful, especially the coccidia, of which sections 

 should be made to show the spores imbedded in the outer 

 skin, and the delicate hexagonal cells of the interior. 



The coccidia are pod-like receptacles at the tips of the 

 filaments, and, when magnified, appear to be dotted with 

 crimson spots. Make a transverse section to observe the 

 position of the spores. The other kind of fructification is 

 a frond covered with sessile capsules, about the- size of a 

 poppy-seed, containing a cluster of oblong red seeds. 



GraciUaria compressa is sometimes cast ashore attached 



to coral and algse at Sidmouth, where it was found by 



Mrs. Griffiths, and also in the Channel Islands by other 



collectors. It is not generally known that the Island of 



* February and March. 



