SYNOPSIS OE SEAWEED TEIBES. 13 



GENERA OE THE LAURENCIA TRIBE. 



©dnneiojsonia — Frond filiform, solid, muck branched; the 

 branches with opposite awl-shaped cilia. 



Laurexcia — Frond cylindrical, or compressed, pinnatified; 

 the ramuli blunt. 



Ghbysymenia — Frond filled with watery gelatine, not con- 

 stricted or chambered. 



Chtlocladia — Frond contracted at intervals, filled with 

 watery gelatine. 



GENERA OF THE CORALLINE TRIBE. 



Sub-order of the Corallines. — Frond filiform, articulated. 



Coralline — Frond pinnated ; ceramidia terminal, simple. 



Jania — Frond dichotomous ; ceramidia tipped with two horns 

 like ramuli. 



Sub-order — Nullipore^e — Frond crustaceous or foliaceous, 

 opaque, not articulated. 



Melobesia — Frond stony, forming either a crustaceous ex- 

 pansion or a foliaceous or shrub-like body. 



Hildenbrandtia — Frond cartilaginous, not stony, forming a 

 crustaceous expansion. 



Hapalidium — Frond plane, transparent, composed of cells 

 radiating from a centre. 



GENERA OF THE DELESSERIA TRIBE. 



Delesseria — Frond leaf-like, of delicate form, with a mid-rib 

 running through it. 



NiTOPHYLLuai — Frond without a mid-rib, delicate, expanded ; 

 sometimes marked with vague veins. 



Plocamium —Frond linear or filiform, much branched, distich- 

 ous : ramuli secund. 



GENERA OF THE RHODYMENIA TRIBE. 



Stenogramme — Conceptacles linear, rib-like; tetraspores col- 

 lected into dense oval well-defined sori. 



