Brain-coral

Brain-coral, or BRAINSTONE CORAL, a popular name for massive corals belonging to the family Astræidae. The windings of their limy framework and their common rounded form have suggested that general resemblance to the convoluted brains of higher animals which the name implies. The name is especially applicable to the genus Mæandrina (M. cerebriformis, sinuossissima, &c.), where the individual animals which compose the colony are arranged in long winding rows. Those of one row are not separated from one another by the usual round walls, and thus elongated continuous furrows are formed not unlike brain convolutions. The entire shape is roughly hemispherical; the rate of growth slow; the total size often large. They are abundant in the West Indian Ocean. About twenty species of Mæandrina are known, some living, others occurring from the chalk on to tertiary strata. See CORAL, MADREPORE.