Abstract: Test apparatus for microbiological cultures includes a vibrating member for placement thereupon of a vessel, such as a petri dish, containing a microbiological culture medium in the form of a liquid film, whereby vibration of the vessel will tend to equalize the thickness of a film formed by solidification of the medium, thereby promoting accuracy of test results. The apparatus further includes a table for placement thereupon of a plurality of vessels containing cultures, the table having a plurality of guides for use in accommodating vessels after removal from the vibrating members. Ramps are disposed on the table adjacent the vibrating members to guide the vessels to the desired position on the vibrating members and to elevate the covers of the vessels so that vibration can occur in a vertical as well as horizontal mode, thereby fostering the desired equalization of the thickness of the culture film in the vessel.