Memorials in Rocks.

Star (Christchurch), Volume LXVI, Issue 20484, 10 December 1934, Page 6

Memorials in Rocks.

Nature Notes

By

James Drummond, F.L.S.. F.Z.S.

JTARD, pure and crystalline limestone

standing like castle walls, in parts fifty feet high, on the shore of Raglan Harbour, West Coast of the North Island, induce Mr P. L. Hill, a resident of the district, to think of the little marine creatures whose remains built up the massive rock. To his mind, rocks that lie in a kowhai grove, which tuis, bellbirds and grey warblers find pleasant places, are memorials in a fitting setting to the limestone-makers, who lived millenniums ago.

Most limestone in the Raglan district seems to have been made by foraminifera, like the stars for multitude, very minute in size, but giving to the world some of the largest and most important limestone, deposits. They played an important part in making chalk in the Cretaceous Period.

Foraminifera still carry on. They are conservatives. The type, unlike types of higher creatures, has neither advanced nor been modified in any material respect since the days of Early Life. Members of one group of them are particularly abundant in the Atlantic Ocean. They are part of the microscopical floating population near the surface called plankton. After they die, their dead shells, chambered, horny, limy, exquisite, sometimes patterned in elaborate designs, fall in hundreds of thousands on to the ocean’s floor, to make a grey ooze that may become solid limestone rock.