338 T. H. BUFFHAM ON THE FLORIDE.E AND 



2. A still more compound fruit containing, or composed of, 

 numerous bodies of similar size to, or smaller than, a tetraspore. 

 To this kind of fruit were given various names according to the 

 structure, form, and position, as ceramidium (urn-shaped), as in 

 Polysiphonia ; coccidium (globose body, frequently half-immersed), 

 as in Plocamium ; favellidinm (globose mass immersed), as in 

 Naccaria ; favella (berry-like), as in Ceramium and Callithamnion. 

 The contained bodies were called spores, and were also found able 

 to originate new plants. These two kinds of fruit were found on 

 most of the species, and if but one was then known it was generally 

 believed that the other existed. 



3. On a few plants were found a curious kind of fruit which 

 Harvey called antheridia in those instances where their position, as 

 in Polysiphonia, was distinct from either the tetraspores or' 

 ceramidia. But in the genus Ccdlithumnion he found some bodies 

 whose structure was similar to that of the antheridia of Polysiphonia, 

 but their position on the ramuli was exactly similar to that of the 

 tetraspores. About these he seemed doubtful, and sometimes 

 suggested the provisional term " viviparous tetraspores." 



In Polysiphonia Jibrata the antheridium is a sausage-shaped 

 body, consisting of numerous minute pale granules developed round 

 a central axis borne on a thin pedicel near the apex of the ultimate 

 ramuli. The appearance suggested a function analagous to that of 

 the anther of a flower, but, as no proof could be given, opinions were 

 divided as to whether the constituents of the antheridium fertilised 

 the germ of a tetraspore or a ceramidium. I believe Harvey's own 

 view was that the fruits containing numerous spores were the pro- 

 duct of such a union. 



These three kinds of fruits were always found on different indi- 

 viduals. 



I may just mention here, with regard to this particular point, 

 that I have found the following sj3ccies containing two kinds of 

 fruit on a plant : — 



Polysiphonia fastigiata : antheridia and ceramidia growing inter- 

 mixed over the whole plant. 

 Plocamivm coccineum ; a fine plant, divided near the base, bearing 



tetraspores on one half and coccidia on the other. 

 Callithamnion tetragonnm : a few favellre on a plant bearing tetra- 

 spores. 

 C. tetrictnn : the same combination. 



