OBSERVATIONS ON A SMALL PORTION OF A DRYING CHALK STREAM
- 1The paper deals with an association of animals found in the drying, but still moist, bed of a chalk stream.
- 2The fauna consists largely of diptera over the wet mud and beetles in patches of stranded algae (Oedogonium). The oligochaet E. tetrahedra is common to both habitats.
- 3The changes in level of the stream and water table are recorded, and it is shown how the capacity of the water table reduces the danger of flooding after rain, which would destroy this habitat.
- 4The significance of this association is discussed with particular reference to the idea that such a habitat may represent the kind of environment in which a terrestrial fauna could evolve towards an aquatic existence.