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lies dry at low tide, thus offering excellent opportunities for studying 
the rich shallow water fauna. All sorts of bottom are represented 
on this flat, rocks, stones, sand, mud, and grass bottom, each sort 
of bottom having its own characteristic fauna. Part of the shore 
is an old coral rock, forming a flat ledge, covered only at high tide. 
The porous rock is inhabited by innumerable boring organisms — 
Molluscs, Gephyreans, Annelids a.o. — while at a slightly lower level, 
which lies dry only at exceptionally low tides, the peculiar boring 
Echinoid Echinostrephus molare is found in deep, cylindrical holes. 
In small pools left on the rock at low tide a small grey Actinian 
is found in great numbers, like a carpet of flowers, each specimen 
attached in a hole in the rock, into which it retracts itself as the 
water disappears. The most interesting feature in the animal com- 
munity peculiar to this locality is, however, the occurrence of some 
large Annelids {Nereis sp. and Marphysa sp.), which from their holes 
in the rocks extend themselves, often for up to two decimeters 
length, over the dry rock, seeking their nourishment in the thin 
coat of microscopical plants which covers the rock. When walking 
