DECAYING SHELLS

Hawke's Bay Herald-Tribune, Issue 12, 29 January 1937, Page 4

DECAYING SHELLS

Horse Mussels in Bed of Inner Harbour Visitors to Napier this summer have been puzzled by a number of decaying shells protuding from the bed of tho inner harbour, which was raised by the eartliquake six years ago. Similar in shape to the mussel which is found clinging to rocks, most of the shells average 12 inches in length, btit ond or two reach 15 inches. Just after the earthquak© thousands of these shells were to b© seen in the mud, but since then many have been removed by the curious and others' have been broken and destroyed. l)r. W. R. B. Oliver identified one of the shells taken from the harbour as being that of jfche horse mussell, or fan mussel. He explained that before the earthquake there were' beds of these mussels in the valley on the Sea bottom, where the animal life on which they fed was evidehtly rich. The mussels were einbedded by their pointed ends straight into the mud up to twothirds of their length, and the remainmg third was covered withi a' dense growth of seaweed and sea animals. . The mussels were raised above the sea by the earthqiiake, and shortly after wards jbhe growth and animals died and fell away, and the decaying shells were left resting perpendicularly in the mud. The mussels are to? be found in practically all harbours in New Zealand with muddy bottoms, and also in othfir parts of the world. The horse mussel really belongs to a dift'erent family from the ordinary mussel, but it is a related family. Both mussels attach thpmselves in exactly the same way by aa bundle of tough threada. The threads of the ordinary mussel attach themselves in a group to a rock, but the horse mussel, which lives in sand or mud. secures its grip by each separate thread fastening on tc grains of gravel. The threads spread out fanwise like the roots of a tree. The animal is in proportion to its shell, and feeds on organisms brought in by the tide. The fibre of the "beard" is tubular like hair, and, when dried, it is sufficently flexible to be woven into gloves and stockings, as was done in parts oi England towards the end of last century.