108 



CORALLINES. 



while it yields spores, contained in receptacles perfectly 

 analogous to those of the 

 Algae of the red series, to 

 which its colour also allies it. 

 These spores were observed 

 and figured by Ellis; and it 

 is therefore the more strange 

 that the vegetable nature 

 of the family has not been 

 earlier acknowledged. Co- 

 rallina officinal is generally 

 occurs in society, covering 

 the bottoms of shallow tide- 

 pools with its jointed fronds, which afford a welcome 

 resting-place to many of the smaller Algse and to marine 

 animals. It always springs from a broad, calcareous 

 base, often of considerable thickness, which incrusts 

 the surface of the rock. It commences to vegetate, 

 though feebly, immediately within the limit of high- 

 water, and extends throughout the whole littoral zone, 

 gradually acquiring fuller development as the water 

 deepens ; and the best specimens are always to be found 

 nearest to low-water-mark. It is occasionally dredged 

 from the depth of three or four fathoms, or perhaps 

 more ; but specimens from water of that depth are less 

 perfect than those collected about low-water-mark, 

 clearly showing that, at that level, the species is in the 

 situation best adapted to its nature. The species of the 

 genus Corallina are very imperfectly known, and many 

 supposed species may ultimately prove to be merely 

 varieties of this common and very generally diffused 



