. ▁ ▁Is olation ▁and ▁identification ▁An ▁easy ▁way ▁to ▁isol ate ▁Bac ill us ▁species ▁is ▁by ▁placing ▁non ster ile ▁soil ▁in ▁a ▁test ▁t ube ▁with ▁water , ▁sh aking , ▁placing ▁in ▁m elt ed ▁man nit ol ▁salt ▁ag ar , ▁and ▁inc ub ating ▁at ▁room ▁temperature ▁for ▁at ▁least ▁a ▁day . ▁Cult ured ▁colon ies ▁are ▁usually ▁large , ▁spread ing , ▁and ▁irregular ly ▁sh aped . ▁ ▁Under ▁the ▁mic ros cope , ▁the ▁Bac ill us ▁cells ▁appear ▁as ▁ro ds , ▁and ▁a ▁substantial ▁portion ▁of ▁the ▁cells ▁usually ▁contain ▁o val ▁end os por es ▁at ▁one ▁end , ▁making ▁them ▁bul ge . ▁ ▁Ph y log eny ▁Three ▁propos als ▁have ▁been ▁presented ▁as ▁representing ▁the ▁ph y log eny ▁of ▁the ▁genus ▁Bac ill us . ▁The ▁first ▁proposal , ▁presented ▁in ▁ 2 0 0 3 , ▁is ▁a ▁Bac ill us - specific ▁study , ▁with ▁the ▁most ▁divers ity ▁covered ▁using ▁ 1 6 S ▁and ▁the ▁I TS ▁regions . ▁It ▁div ides ▁the ▁genus ▁into ▁ 1 0 ▁groups . ▁This ▁includes ▁the ▁nested ▁gener a ▁Pa en ib ac ill us , ▁Bre v ib ac ill us , ▁Ge ob ac ill us , ▁Mar in ib ac ill us ▁and ▁Vir g ib ac ill us . ▁ ▁The ▁second ▁proposal , ▁presented ▁in ▁ 2 0 0 8 , ▁ ▁constructed ▁a ▁ 1 6 S ▁( and