<prompt> Swarming growth on culture is characteristic of which Gram-negative organism -Clostridium welchiiClostridium tetaniBacillus cereusProteus mirabilis  <response>: Pr.mirfabilis Pr.vulgaris swarms on solid culture media .discrete colonies are seen in young cultures but thereafter actively motile cells spread on the surface of the plate in successive waves to form a thin film layer in concentric circles. REF:Ananthanarayan Panickers Textbook of Microbiology 8th edition pg no:280-281 