After streaking, the medium can then be left to incubate at 36°C for 1 day, and then be inspected for roughly 2mm wide, white, or off-white circular colonies, often with curling tails at the edges \cite{turnball}. Despite the selectivity of the media, some bacteria, including Staphylococcus and some Bacillus strains are able to survive on the PLET media, so for a full diagnostic result, the colonies will have be to individually tested for traits such as penicillin toxicity, lack of motility and susceptibility to γ-phage to confirm species as being Bacillus anthracis \cite{Driks_2009}