Further south, along the cliffs of the Indo-China peninsula, in the 

 upper portion of the intertidal zone there are few algae, but a rich 

 population of settled animals (actinea, serpulids, the barnacles 

 Tetrad i ta porosa , Balanus and Chthamal us , complex ascidians, the 

 oysters Ostrea forskal i and _0. spinosa ) , and in the lower portion the 

 algae Turbinaria , Padina , sargassums and calcareous red algae such as 

 Melobesia develop (Fischer, 1952). 



In Indonesia, the Nerita rise quite high in the intertidal zone. 

 The distribution of fauna is quite variegated and mosaic. The 

 overwhelming portion of the intertidal zone carries low biomass--a few 

 grams, less frequently a few tens of grams per m^ (Mokiyevskiy , 1967). 



Along the coast of northern and northeastern Australia, there dre 

 extensive coral reefs extending into the intertidal zone. In the upper 

 portion of the intertidal zone itself are settlements of Chthamal us ma- 

 layensis and Ch. withersii with occasional isopods. Below this are 

 bands of Crassostrea amasa . Tetrad ita squamosa and a narrow band of 

 Acanthozostera and Liolophura or Acanthopleura . Still lower we see the 

 simple ascidians ( Microcosmus austral is ), Chthamalus caudatus . 

 Tetrad ita costata , sponges, Siliquaria ponderosa , crabs, holothurians 

 and the algae Valonia and Padina (Stephenson, Stephenson, 1972). In 

 southern Australia and Tasmania, settlements of Chamaesipho columna . 

 Chthamalus antennatus and Catophragmus polymerus develop, plus bands of 

 Modiolus pulex and Brachyodonte rostratus . In the lower portion of the 

 intertidal zone there is usually a band of Galeolaria caespitosa 

 (Bennet, Pope. 1953). 



Along the intertidal zone of the Subantarctic island of Macquariae, 

 there are apparently no barnacles; the most characteristic vegetation is 

 Porphyra umbil ical is with some Ulva lactuca . Enteromorpha intestinal is 

 and other algae. The lower portion is dominated by Rhodymenia . Of the 

 animals, the gastropods Siphonaria lateralis , Nacella delesseri and 

 Macquariella hamiltoni are most common (Stephenson, Stephenson, 1972). 



The sublittoral or infral i ttoral edge . This level usually occupies 

 the lower portion of the zone which dries out, and when the surf is weak 

 corresponds to the lower stage of horizon III of the intertidal zone. 

 Independent communities are formed rather rarely here; more frequently, 

 communities of the upper sublittoral simply extend into the zone. 

 However, due to the drying of the edge, though it may be brief, its 

 population differs from the sublittoral population; first of all, the 

 specific composition is much more sparse. Secondly, certain strictly 

 littoral species are present. In cold and temperate waters, large 

 laminaria algae predominate, while in warm waters we usually see the 

 upper boundary of the colonies of corals, dense clusters of the ascidian 

 Pyura , and stands of Sargassums and red algae are encountered; at all 

 latitudes, calcareous Rhodophyta are seen here, belonging to various 

 genera, but usually called 1 i thothamnion (cortical and branched, nonseg- 

 mented forms) and corallina (branched segmented forms). Frequently, in 

 warm waters, these calcareous red algae develop quite rapidly and form 

 massive "bridges" or "trotoires" (in the Mediterranean) or even entire 

 reefs (in the tropics). The porous or spongy thallomes of these plants 

 provide shelter for numerous cryptofauna. In warm waters, calcareous 



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