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Pelorus Guardian and Miners' Advocate., Volume 22, Issue 90, 21 November 1911, Page 5

j PLANTS WITH “POP-GUNS."— , Professor Cavers has just described a ! mechanism which .is unique in the | world of plants. It is that by I which the peat-mosses (which have no seeds) effectively spread the tiny bodies or spores, by which they, like ! many of the lower plants, are repro j duced. Tne spores are contained in a capsule, which is at first like a ball I in shape, and arc confined to an up? I per chamber, while a lower one bcj comes filled only with air. As the I capsule ripens, it shrinks, taking upI on itself a cylindrical form, and boj cessarily the air .inside it becothes ( more compressed. As a matter! oi fact, the pressure within may be 'six times as great as that of the atmosphere without. Round the top' of, the capsules is a groove which exists for much the same reason as thin place made in the tope of tins in which meat is preserved, namely,; to allow of their being opened easily.' The part of the capsule within the groove, whichi is to form the lid, does not shrink quite so greatly as the rest, and a strain is set up so that then,says the Professor, in “Knowledge,” the compressed air explodes in just the same manner as that from a child’s pop-gun and blows out the spores. 1777.