Geocarpy is `an extremely rare means of plant reproduction`, in which plants produce diaspores within the soil. This may occur with subterranean flowers (protogeocarpy), or from aerial flowers, which penetrate the soil after flowering (hysterocarpy). It has evolved as an effective means of ensuring a suitable environment for the plant`s offspri...... Found on http://en.wikipedia.org/wiki/Geocarpy
(from the article `seed and fruit`) ...of an already occupied, favourable site. This aim is often achieved by synaptospermy, the sticking together of several diaspores, which makes them ... Found on http://www.britannica.com/eb/a-z/g/21