Ascilla is a tubular, branched calcium-containg sponge currently known as Leucoselenia. Multiple sponge stalks are anchored by one common root to the ocean floor. The stalks take up water through microscopic holes on their surface and expel it through a hole on the end of the stalk, like a mass of fire hoses. Hatched larvae are also expelled from this hole, swimming until they find a suitable place to attach and form a new sponge. Ernst Haeckel described the organism as “a racemose cane, whose slender stalks have the shape of a graceful urn.” This sponge is often found in tide pools, clinging to seaweed or rocks.