Just like the shell of a clam, a pearl is composed of calcium carbonate (mainly aragonite or a mixture of aragonite and calcite). in minute crystalline form, which has been deposited in concentric layers. The ideal pearl is perfectly round and smooth, but many other shapes, known as baroque pearls, can occur.
Rimula is a genus of fungi in the Helotiales order. The relationship of this taxon to other taxa within the order is unknown (incertae sedis), and it has not yet been placed with certainty into any family. ^ Lumbsch TH, Huhndorf SM. (December 2007). Outline of Ascomycota â 2007.
Also found in: Dictionary, Encyclopedia, Wikipedia. lingula. a small, tonguelike anatomical structure. adj., adj lingÂ´ular. lingula of cerebellum the most ventral part of the anterior lobe of the cerebellum. lingula of left lung a small projection from the lower portion of the upper lobe of the left lung. lingula of sphenoid the bony ridge between the body and the great wing of the sphenoid bone.