Test tube for easy enumeration and cultivation of anaerobic and facultatively anaerobic microorganisms

摘要

A test tube having an inner tube that allows one to insert a bar to create a dark background is described. This system is actually an ordinary or screw-capped test tube with a smaller sized test tube inverted and fused to the bottom. The design permits a thin layer of any agar medium to solidify around the inside edge of the larger tube. The colonies developed in the agar can then be easily counted by creating a dark background by inserting a dark colored rod through the opening of the inner tube.