(from the article `ark shell`) ...of the 200 or so known species are found in tropical seas, with relatively few occurring in temperate areas. Ark shells are slow-moving or ... Found on http://www.britannica.com/eb/a-z/a/94
[NGO] Asociația Română pentru Cosmonautică și Aeronautică (ARCA) or Romanian Cosmonautics and Aeronautics Association is a non-governmental organization that promotes aerospace projects as well as other space-related activities. It is based in Râmnicu Vâlcea, Romania. == Private space program == ARCA announced in March 2012 that it ... Found on http://en.wikipedia.org/wiki/ARCA_(NGO)
Associate of the Royal Cambrian Academy(ARCA). Founded in 1826 the RCA claims no one knows what the true definition of Welsh Art is, but if it exists, it can be seen at the Royal Cambrian Academy.
Found on http://www.redraggallery.co.uk/art-glossary.html