The Victorian naturalist . wink, Bembiciumnanum, reached its maximum not confined to this zone, itwas noted rarely in the lower littoraland its numbers fell off toward high tide level. It was in this zone also thatthe black-green threads of the lichen,Lichina confinis, gave a dark colour-ation to the rock surface, and the tallcones of Cellana became prominent. Zone 4. The Melarapha zone. Upperand supra-littoral, 1-0-2 -25 metreabove low tide. The appearance of the blue-greyspirals of Melarapha praetermissaindicated this zone. At its lowerextremity, Bembicium nanum still oc-cur
The Victorian naturalist . wink, Bembiciumnanum, reached its maximum not confined to this zone, itwas noted rarely in the lower littoraland its numbers fell off toward high tide level. It was in this zone also thatthe black-green threads of the lichen,Lichina confinis, gave a dark colour-ation to the rock surface, and the tallcones of Cellana became prominent. Zone 4. The Melarapha zone. Upperand supra-littoral, 1-0-2 -25 metreabove low tide. The appearance of the blue-greyspirals of Melarapha praetermissaindicated this zone. At its lowerextremity, Bembicium nanum still oc-curred and a few specimens ofLepsiella vinosa appeared. Malaraphaunifasciata, present in minute formand large numbers from mid-littoralshowed here as larger specimens whichpersisted for several metres above hightide level. Inconspicous inhabitants The most conspicuous species of therock platform have been described andin this instance the noticeable specieswere not present in large until the rock face was examined. closely was it seen that incrediblenumbers of minute gastropods coveredmost of its surface. Melarapha paludi-nella, like specks of black coal dustappeared at the rate of about onequarter million per square metre. Theslightly larger brown shells ofMelarapha unifasciata covered mostof the rock face from mid-littoral tothe supra-littoral at the rate of 75,000per square metre. In all, each squaremetre of rock face was the site forover 3,000,000 specimens! Some notable absentees There were some interesting absen-tees from this platform, particularlychitons and anemones. This wasprobably due to the particular position and topography of this platform, sincefifty metres away on an exposed ver-tical cliff, anemones occurred at therate of 20 per square metre andchitons at 8 per square metre. Conclusion Sufficient has been said here tocaution any who would generalizefrom the elementary observationsrecorded. Generalizations about theecology of the seashore can only bema
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Keywords: ., bookcentury1800, bookdec, booksubjectnaturalhistory, bookyear1884
